Practice Test

Q1) Wavelength of the wave is the distance between two particles of the medium having a phase difference of : Show Answer

Q2) Longitudinal waves cannot be propagated through: Show Answer

Q3) The velocity of sound is measured in hydrogen and oxygen at a certain temp. The ratio of the velocities is: Show Answer

Q4) Sound travels in rocks are in the form of: Show Answer

Q5) The longitudinal and transverse waves can be distinguished by studying the property of: Show Answer

Q6) When a wave is reflected from a rigid surface, it undergoes a phase change given by: Show Answer

Q7) The intensities of sound are in the ratio 1 : 16 for two waves of same frequency and travelling in same medium. Their amplitudes are in the ratio: Show Answer

Q8) The sound generator dipped in sea is sending waves of wavelength 2.5 m and frequency 580 Hz. The velocity of sound in sea water is: Show Answer

Q9) Transverse waves are generated in two steel wires A and B with a source of 512 Hz. If their diameters are in the ratio 2 : 1 and tensions in the ratio 2 : 1, the velocities of the waves are in the ratio: Show Answer

Q10) An observer at sea coast sees 54 waves striking a rock per minute. If wavelength is 10 m, what is the velocity of wave? Show Answer

Q11) The amplitude of sound waves corresponding to normal conversation of human beings is of the order of: Show Answer

Q12) Under similar conditions of temperature and pressure, in which of the following gases will the velocity of sound be least? Show Answer

Q13) A string when stretched with a weight of 9 kg weight produces a note of frequency 256. Calculate the weight to produce an octave of the note: Show Answer

Q14) Stationary waves of frequency 200 are formed in air. If velocity of the wave is 360 m/s the shortest distance between anti-nodes will be: Show Answer

Q15) When a tuning fork beings to vibrate, the vibrations of its two prongs: Show Answer

Q16) When stationary waves are set up, which of the following statements is applicable? Show Answer

Q17) Two sources of intensities ratio 25 : 1 interfere. The ratio of intensities at maxima and minima will be: Show Answer

Q18) In the production of beats by the two waves of same amplitudes and nearly same frequencies, the maximum loudness heard corresponding to each of the constituent wave is: Show Answer

Q19) A fork gives 5 beats with a 40 cm length of sonometer wire. If the length of the wire is shortened by 1 cm, the number of beats is still the same. The frequency of the fork is: Show Answer

Q20) A certain string will resonate to several frequencies, the lowest of which is 200 Hz. What are the next three higher frequencies to which it resonates? Show Answer

Q21) A string of 0.3 m length is found to resonate in 3 segments (nodes at both ends) when the driving frequency is 20 Hz. The speed of the wave in the spring is: Show Answer

Q22) The string of violin has a frequency of 440 Hz. If the violinist shortens the string by one-fifth, by fingering it, its frequency will be changed by: Show Answer

Q23) A wire of sonometer is 1 m in length and has a fundamental frequency of 330 Hz. The velocity of transverse waves along the wire is: Show Answer

Q24) Two wires A and B and stretched between two points. The diameter, tension and density of B are twice that of A. The ratio of frequency B to that of A is: Show Answer

Q25) A wire under tension vibrates with a frequency of 450 Hz. What would be the fundamental frequency if the wire were half as long, twice as thick and under one-fourth tension: Show Answer

Q26) If the frequency of the vibration of a string is increased by a factor of two, then the tension in the string should be: Show Answer

Q27) A closed end organ pipe has a frequency of 100 Hz as its fundamental note. The frequency of third harmonic will be: Show Answer

Q28) An open end organ pipe of fundamental frequency 550 Hz is filled with hydrogen, its frequency will: Show Answer

Q29) In resonance tube two position of resonance are obtained at 15 cm and 48 cm. If the frequency of the fork is 500 Hz, the velocity of sound is: Show Answer

Q30) A closed pipe of 10 cm length has its fundamental, half that of the second overtone of an open end pipe, find the length of the pipe: Show Answer

Q31) A tube of glass open at both ends, has a fundamental frequency in air, the tube is dipped vertically in water so that half of it is in water. The frequency of air column is: Show Answer

Q32) If the source moves away with such a velocity from listener, who is at rest that frequency of the note is halved, then its velocity is (velocity of sound = 332 m/s): Show Answer

Q33) The intensity of sound gets reduced by 20% on passing through a wall. The reduction of intensity on passing through two consecutive similar walls will be: Show Answer

Q34) A source of sound that is emitting a frequency of 450 cycles/second is approaching a stationary observer with a speed of 34 metres/second. If the speed of sound in air is 340 metres/second the apparent frequency heard by the observer is: Show Answer

Q35) A motor cyclist moving with 30 km/hr blows a whistle of 476 Hz towards a cliff. If velocity of sound is 1220 km/hr, the apparent frequency of the echo heard by him is: Show Answer

Q36) An engine standing at the platform blows a whistle of frequency 305 vib/sec. If the velocity of sound be 1220 km/hr, the frequency of the whistle as heard by a man running towards the engine with a speed of 20 km/hr is: Show Answer

Q37) The wavelength of light coming from a star shifts towards the violet end of the spectrum.
This shows that the star is: Show Answer

Q38) Ultrasonics are used for stirring liquid solutions in order to produce: Show Answer

Q39) The speed of longitudinal wave in a thin brass rod is 3480 metre/second. If the rod clamped at one end gives a fundamental frequency of 435 cycles/second, the length of the rod is: Show Answer

Q40) A wave of frequency 100 Hz travels along a string towards its fixed end. When this wave travels back, after reflection, a node is formed at a distance 10 cm from the fixed end. The speed of the wave (reflected and incident) is: Show Answer

Q41) For a certain organ pipe three successive harmonics are 425, 595 and 765 Hz. What is the fundamental frequency? Show Answer

Q42) On producing waves of frequency 1000 Hz in a gas filled kundt's tube, the total distance between 6 successive nodes is 82.5 cm. Find the speed of sound in the gas? Show Answer

Q43) A uniform rope of mass 0.1 kg and length 2.45 m hangs from the ceiling. Find the speed of transverse waves at a point 0.5 m distant from the lower end. Show Answer

Q44) A uniform rope of mass 0.1 kg and length 2.45 m hangs from the ceiling. Find the speed of transverse waves at a point 0.5 m distant from the lower end.calculate the time taken by the wave to travel full length of the rope: Show Answer

Q45) Standing waves are produced in 10 m long stretched string. If the string vibrates in 5 segments and the wave velocity is 20 m/s, the frequency is: Show Answer

Q46) An observer is watching two vehicles of same velocity (4 m/s). The former is approaching towards the observer while the later receding. If the frequency of the siren of the vehicle is 240 Hz and velocity of sound in air is 320 m/s, then the beats produced is: Show Answer

Q47) Resonance is a special case of: Show Answer

Q48) Which waves are used in sonography? Show Answer

Q49) If the temperature increases, then what happens to the frequency of the sound produced by the organ pipe? Show Answer

Q50) If a wave enters from air to water, then what remains unchanged? Show Answer

Q51) A string oscillating at fundamental frequency under a tension of 225 N produces 6 beats per second with a sonometer. If the tension is 256 N, then again oscillating at fundamental note is produces 6 beats per second with the same sonometer. What is the frequency of the sonometer? Show Answer

Q52) The length of a sonometer wire AB is 110cm. Where should the two bridges be placed from A to divide the wire in 3 segments whose fundamental frequencies are in the ratio of 1 : 2 : 3? Show Answer

Q53) A weight is attached to the free end of a sonometer wire. It gives resonance at a length of 40 cm when it is resonanced with a tuning fork of frequency 512. The weight is then immersed wholly in water, the resonant length is reduced to 30 cm. The relative density of the fluid in which weight suspended is: Show Answer

Q54) Two open organ pipes of length 50 cm and 50.5 cm produce 0.3 beats/sec. Then the velocity of sound is: Show Answer

Q55) In stationary wave the strain is: Show Answer

Q56) A wave of frequency 100 Hz is sent along a string towards of fixed end. When this wave travels back after reflection, a node is formed at a distance of 10 cm from the fixed end of the string. The speed of incident (and reflected) wave are: Show Answer

Q57) A glass tube of 1.0 m length is filled with water. The water can be drained out slowly at the bottom of the tube. If a vibrating tuning fork of frequency 500 c/s is brought at the upper end of the tube and the velocity of sound is 330 m/s, then the total number of resonances obtained will be: Show Answer

Q58) A long glass tube is held vertically in water. A tuning fork is struck and held over the tube. Strong resonances are observed at two successive lengths 0.50 m and 0.84 m above the surface of water. If the velocity of sound is 340 m/s then the frequency of the tuning fork is: Show Answer

Q59) A source of sound S is moving with a velocity 50 m/s towards a stationary observer. The observer measures the frequency of the source as 1000 Hz. What will be the apparent frequency of the source when it is moving away from the observer after crossing him? The velocity of sound in the medium is 350 m/s. Show Answer

Q60) If the intensity of sound is doubled, the sound level will increase by nearly: Show Answer

Q61) A jet plane travels at Mach 2 at an altitude of 1600 m. How far past an observer will the plane be when the shock wave hits him? Show Answer

Q62) The intensity level due to two waves of the same frequency in a given medium are 1 bel and 5 bel. Then the ratio of amplitudes is: Show Answer

Q63) Two trains A and B approach a stationary observer from opposite sides with speeds 15 m/s and 30 m/s respectively. Observer hears no beats. If frequency of whistle of train B is 504 Hz, the frequency of whistle of A is (speed of sound = 330 ms): Show Answer

Q64) A radio wave of frequency 840 MHz is sent towards an aeroplane. The frequency of radio echo has a frequency 2.8 kHz more than the original frequency. Then the velocity of the aeroplane is: Show Answer

Q65) The number of waves contained in a unit length of the medium is called: Show Answer

Q66) Two waves 50 cm and 51 cm is wavelengths produce 12 beats/sec. The velocity of sound is: Show Answer

Q67) In a wave the time required for a particular point to move from max. displacement to zero displacement is 0.170 second. The frequency of the wave is: Show Answer

Q68) Mechanical waves on the surface of a liquid are: Show Answer

Q69) In the open organ pipe the fundamental frequency is 30 vibrations/second. If the organ pipe is closed, then the fundamental frequency will be: Show Answer

Q70) Two whistles A and B produces notes of frequencies 660 Hz and 596 Hz respectively. There is a listener at the middle point of the line joining them. Both the whistles B and the listener start moving with speed 30 m/s away from the whistle A. If speed of sound be 330 m/s, how many beats will be heard by the listener? Show Answer

Q71) Two sirens situated one kilometre apart are producing sound of frequency 330 Hz. An observer starts moving from one siren to the other with a speed of 2 m/s. If the speed of sound be 330 m/s, what will be the beat frequency heard by the observer? Show Answer

Q72) An observer is watching two vehicles of same velocity (4m/s). The former is approaching towards the observer while the later receding. If the frequency of the siren of the vehicle is 240 Hz and velocity of sound in air is 320 m/s, then the beats produced is: Show Answer

Q73) Which one is not produced by sound waves in air? Show Answer

Q74) A pulse or a wavetrain travels along a stretched string and reaches the fixed end of the string. It will be reflected back with: Show Answer

Q75) What is frequency of radio waves transmitted by a station, if the wavelength of these waves is 300 m? Show Answer

Q76) The combination of two or more notes which produces a melodious effect on ear is called: Show Answer

Q77) Energy is not carried by: Show Answer

Q78) In a sinusoidal wave, the time required for a particular point to move from maximum displacement to zero displacement is 0.170 s. The frequency of the wave is: Show Answer

Q79) Two trains, one coming towards and another going away form an observer both at 4 m/s, blow whistles simultaneously giving sounds of frequency 300 Hz. Find the number of beats produced. Show Answer

Q80) The apparent frequency of a note, when a listener moves towards a stationary source, with velocity of 40 m/s, is 200 Hz. When he moves away from the same source with the same speed, the apparent frequency of the same note is 60 Hz. The velocity of sound in air is (in m/s) is: Show Answer

Q81) The velocity of sound is greatest in: Show Answer

Q82) The Doppler's effect is applicable for: Show Answer

Q83) A sonometer wire stretched with 64 newton is vibrating in its fundamental tone and in resonance with a vibrating tuning fork. Length of the vibrated part of sonometer wire is 10 cm and the mass is 1 gram. Vibrating tuning fork is brought far away from vibrated wire with a constant speed and an observer standing near the sonometer hears 1 beat per second. If the speed of sound in the air is 300 m/s then speed of tuning fork will be: Show Answer

Q84) 26 tuning forks are placed in a series such that each tuning fork produces 4 beats with its previous tuning fork. If the frequency of last tuning fork be three times the frequency of first tuning fork, then frequency of first tuning fork will be: Show Answer

Q85) A stretched wire, 60 cm long is vibrating with its fundamental frequency 256 Hz. If the length of the wire is decreased to 15 cm, and the tension remains the same, then the fundamental frequency of the vibration of the wire will be: Show Answer

Q86) The velocity of sound in air depends upon: Show Answer

Q87) A tuning fork produces 4 beats/sec. with another fork of frequency 288 cps. A little wax is placed on the unknown fork and it then produces 2 beats/sec. The unknown frequency is: Show Answer

Q88) A tuning fork of known frequency 256 Hz makes 5 beats per second with the vibrating string of a piano. The beat frequency decreases to 2 beats/sec when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was: Show Answer

Q89) If the pressure amplitude in a sound wave is tripled, then the intensity of sound is increased by a factor of: Show Answer

Q90) Standing waves are produced in a 10 m long stretched string. If the string vibrates in 5 segments and the wave velocity is 20 m/s, the frequency is: Show Answer

Q91) The fact that light of transverse wave derives its evidence by the support from the observation that: Show Answer

Q92) In a transverse progressive wave of amplitude A, the maximum particle velocity is four times its wave velocity, then the wavelength of the wave is: Show Answer

Q93) A source and an observer move away from each other, with a velocity of 10 m/s with respect to ground. If the observer finds the frequency of sound coming from the source as 1950 Hz. Then actual frequency of the source is (velocity of sound in air = 340 m/s): Show Answer

Q94) A resonance air column of length 20 cm resonates with a tuning fork of frequency 250 Hz. The speed of sound in air is: Show Answer

Q95) Which of the following is not a transverse wave? Show Answer

Q96) A stone is dropped into a lake from a tower 500 metre high. The sound of the splash will be heard by the man approximately after: Show Answer

Q97) A tuning fork vibrates with two beats in 0.4 second, the frequency is: Show Answer

Q98) The tension in a piano wire is 10 N. What should be the tension in the wire to produce a note of double the frequency? Show Answer

Q99) A siren emitting sound of frequency 800 Hz is going away from a static listener with a speed of 30 m/s. The frequency of sound heard by listener is (velocity of sound = 300 m/s): Show Answer

Q100) A siren placed at a railway platform is emitting sound of frequency 5 kHz. A passenger sitting in a moving train A records a frequency of 5.5 kHz, while the train approaches the siren. During his return journey in a different train B, he records a frequency of 6.0 kHz, while approaching the same siren. The ratio of velocity of train B to the velocity of train A is: Show Answer

Q101) A sonometer wire resonants with a given tuning fork forming standing waves with five antinodes between the two bridges when a mass of 9 kg is suspended from the wire. When this mass is replaced by mass M, the wire resonates with the same tuning fork forming three antinodes for the same position of bridges. The value of M is: Show Answer

Q102) A string in a musical instrument is 50 cm long and its fundamental frequency is 800 Hz. If a frequency of 1000 Hz is to be produced, then required length of string is: Show Answer

Q103) In a stationary waves are variation in pressure at nodes is: Show Answer

Q104) A police car moving at 22 m/s chases a motor cyclist. The policeman sounds his horn at 176 Hz, while both of then move towards a stationary siren of frequency 165 Hz. Calculate the speed of motor cycle if it is given that he does not observe any beats. Show Answer

Q105) In the experiment for the determination of speed of sound in air using the resonance column method, the length of the air column that resonates in the fundamental mode, with a tuning fork is 0.1 m. When this length is changed to 0.35 m, the same tuning fork resonates with the first overtone. Calculate the end correction: Show Answer

Q106) If two tuning forks A and B are sounded together, they produce 4 beats per second. A is then slightly loaded with wax, they produce less beats when sounded again. The frequency of A is 256 Hz. The frequency of B will be: Show Answer

Q107) A stone is hung in air form a wire which is stretched over a sonometer. The bridges of the sonometer are 40 cm apart when the wire is in unison with a tuning fork of frequency 256. When the stone is completely immersed in water, the length between the bridges is 22 cm for re-establishing unison. The specific gravity of the material of the stone is: Show Answer

Q108) The intensity of a sound wave while passing through an elastic medium falls down to 10% as it covers one metre distance through the medium. If the initial intensity of the sound wave was 100 decibels, its value after it has passed through 3 metre thickness of the medium will be: Show Answer

Q109) If fundamental frequency of closed pipe is 50 Hz, then frequency of second overtone is: Show Answer

Q110) A source of frequency 150 Hz is moving in the direction of a person with a velocity of 110 m/s. The frequency heard by the person will be (speed of sound in medium = 330 m/s): Show Answer

Q111) The waves produced by a motorboat, sailing in water, are: Show Answer

Q112) An organ pipe enclosed at one end has fundamental frequency of 1500 Hz. The maximum number of overtones generated by this pipe which a normal person can hear is: Show Answer

Q113) Which of the following emit a pure sine wave? Show Answer

Q114) When tuning fork is vibrating the vibrations of two tuning prongs: Show Answer

Q115) A source of sound of frequency 600 Hz is placed inside water. The speed of sound in water is 1500 m/s, and in air, it is 300 m/s. The frequency of sound recorded by an observer who is standing in air is: Show Answer

Q116) A point source emits sound equally in all directions in a non-absorbing medium. Two points P and Q are at distances of 2 m and 3 m respectively from the source. The ratio of the intensities of the waves at P and Q is: Show Answer

Q117) A tuning fork of 512 Hz is used to produce resonance in a resonance tube experiment. The level of water at first resonance is 30.7 cm and at second resonance is 63.2 cm. The error in calculating velocity of sound is: Show Answer

Q118) Two tuning forks have frequencies 450 Hz and 454 Hz respectively. On sounding these forks together, the time integral between successive maximum intensities will be: Show Answer

Q119) A source of sound S is moving with a velocity 50 m/s towards a stationary observer. The observer measures the frequency of the source as 1000 Hz. What will be the apparent frequency of the source when it is moving away from the observer after crossing him? The velocity of sound in the medium is 350 m/s.
Show Answer

Q120) Twenty six tuning forks are arranged in order of decreasing frequencies. Each fork gives 3 beats with the adjoining fork. Given that first is octave of the last then the frequency of 18th fork is: Show Answer

Q121) A boat at anchor is rocked by waves whose crests are 100 m apart and velocity is 25 m/s. The boat bounces up once in every: Show Answer

Q122) Two points are located at a distance of 10 m and 15 m from the source of oscillation. The period of oscillation is 0.05 sec.and velocity of wave is 300 m/sec. What is phase difference between the oscillations of two points? Show Answer

Q123) Each of the two strings of length 51.6 cm and 49.1 cm are tensioned separately by 20 N force. Mass per unit length of both the strings is same and equal to 1 g/m. When both the strings vibrate simultaneously the number of beats is: Show Answer

Q124) A tuning fork of frequency 512 Hz makes 4 beats per second with the vibrating string of a piano. The beat frequency decreases to 2 beats per sec when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was: Show Answer

Q125) Sound waves travel at 350 m/s through a warm air and at 3500 m/s through brass. The wavelength of a 700 Hz acoustic wave as it enters brass from warm air. Show Answer

Q126) At a certain instant, a stationary transverse wave is found to have maximum kinetic energy. The appearance of the string at that instant is Show Answer

Q127) Sound waves of frequency 660 Hz and travelling with a velocity of 330 m/s are incident normally on a perfectly reflecting wall. The shortest distance at which the air particles have the maximum amplitude of vibration is Show Answer

Q128) A stationary sound wave has a frequency of 165 Hz. If the speed of sound in air is 330 m/s, then the distance between a node and the adjacent antinode is Show Answer

Q129) A stationary wave is incident on a rigid wall. If the velocity of the wave is 40 m/s and the frequency is 120 Hz, then the distance between the wall and the first antinode is Show Answer

Q130) A standing wave with a number of loops is produced in a string fixed at both ends. In this case Show Answer

Q131) In stationary wave the Show Answer

Q132) The phase at different points in a stationary wave are Show Answer

Q133) Two sinusoidal waves having the same wavelength and amplitude travel along a string in opposite directions, with a speed of 5 m/s. What is the wavelength of the wave, if the minimum time interval between two instants, when the string becomes flat, is 0.8 s? Show Answer

Q134) If the tension in a string is increased from T to 4 T, by keeping other factors constant, then the frequency of the string will Show Answer

Q135) If the length and diameter of a wire are decreased, then for the same tension the natural frequency of the stretched wire Show Answer

Q136) A sonometer wire is emitting a note of frequency n, when stretched by a weight. If the weight is completely immersed in water, then the frequency of the wire Show Answer

Q137) When a sonometer wire vibrates in the second overtone, there are Show Answer

Q138) A stretched string is in resonance with a tuning fork of frequency 250 Hz. If the distance between two consecutive antinodes on the string is 5 cm, then the velocity of the progressive wave in the string is Show Answer

Q139) A sonometer wire is in unison with a tuning fork of frequency 256 Hz, when the length of the wire between the bridges is 75 cm and only one loop is formed. By keeping the length and tension constant, the wire is made to vibrate with 2 loops. The wire can still be in resonance with a tuning fork, provided the frequency of the tuning fork is Show Answer

Q140) A stretched sonometer wire of length 1 metre has a fundamental frequency of 50 Hz. If it is plucked at 25 cm, by keeping the bridge at 50 cm, the frequency of vibration of the stretched string would be, Show Answer

Q141) The fundamental frequency of a wire stretched with a 2 kg wt is 100 Hz. The weight required to produce its octave will be Show Answer

Q142) The frequency of the second harmonic emitted by a wire is 200 Hz. The frequency of the third overtone produced by the wire will be Show Answer

Q143) Stationary waves are produced in a stretched string of length 120 cm. If the string vibrates with 6 segments and if the frequency of vibration of the string is 20 Hz, then the velocity of waves on the string is Show Answer

Q144) A sonometer wire of length 0.7 m is stretched by a weight of 4 kg. What is the linear density of the material of the wire, if its fundamental frequency is 200 Hz? Show Answer

Q145) If we want to increase the frequency of transverse oscillations of a stretched string by 50%, the tension must be increased by Show Answer

Q146) The length of a sonometer wire is doubled and the tension is increased four times. The frequency will Show Answer

Q147) A stretched string resonates with a tuning fork of frequency 500 Hz, when the length of the string is 0.75 m. If a tuning fork of frequency 250 Hz is used, then the new resonating length will be Show Answer

Q148) The frequency of transverse vibrations on a stretched string is 150 Hz. If the tension is increased four times and length is reduced to one fourth of its original value, the frequency of vibrations will be Show Answer

Q149) In a stretched wire under tension and fixed at both ends, the area of cross section of the wire is halved and the tension is doubled. The frequency of the wire will be Show Answer

Q150) A string of length L fixed at both ends vibrates in its first overtone. Then the wavelength will be Show Answer

Q151) An additional load of 6 kg on a string makes its pitch double the fundamental. What was the initial tension in the string? Show Answer

Q152) The velocity of waves in a string fixed at both ends is 3 m/s. The string forms standing waves with nodes 6 cm apart. The frequency of vibration of the string is Show Answer

Q153) A stretched string of length L fixed at both ends can sustain stationary waves of wavelength lambda given by
where n is a whole number. Show Answer

Q154) A stretched string resonates with a tuning fork of frequency 480 Hz, when the length of the string is 60 cm. The length of the same string required to vibrate resonantly with a tuning fork of frequency 240 Hz will be Show Answer

Q155) A sonometer wire with a suspended mass of M = 2 kg is in resonance with a tuning fork. The apparatus is taken to the moon where the acceleration due to gravity is 1/6th that on the earth. To obtain resonance on the moon, the value of M should be Show Answer

Q156) Three wires of identical lengths, diameters and material are stretched on a sonometer box. If their tensions are in the ratio of 1:9: 16, then the ratio of their fundamental frequencies will be Show Answer

Q157) A transverse disturbance is sent along a sonometer wire of length 1m, and linear density of 0.25 gram/metre, stretched with a tension of 10 N. What is the time taken by the transverse disturbance to travel along the wire? Show Answer

Q158) A stretched wire of length 30 cm emits a note of frequency 200 Hz, when plucked at its centre. By keeping its tension constant, the length of the wire is decreased by 5 cm. Then it will emit a sound note of frequency Show Answer

Q159) A vibrating tuning fork and a vibrating sonometer wire of length 30 cm produce 4 beats/sec. If the length of the wire is increased to 32 cm, again 4 beats/sec. are heard. What is the frequency of the tuning fork? Show Answer

Q160) A string of length 2 m is fixed at both ends. If this string vibrates in its fourth normal mode, with a frequency of 500 Hz, then the waves would travel on the string with a velocity of Show Answer

Q161) A tuning fork of frequency 500 Hz produces 8 beats/ second when sounded with a vibrating sonometer wire. What must be the frequency of the sonometer wire, if a slight increase in its tension produces fewer beats per second than before? Show Answer

Q162) A sonometer wire stretched by a tension of 1.5 kg weight, has the fundamental frequency of 256 Hz. How much additional weight should be placed on the hanger, in order to produce its octave? Show Answer

Q163) The vibrations of a stretched string consists of Show Answer

Q164) The velocity of propagation of transverse waves on a stretched wire will be doubled if (keeping all other factors the same), Show Answer

Q165) A tuning fork produces 5 beats/sec with a sonometer wire of length 78 cm. If the length of the wire is increased by 2 cm, then there is a resonance between the tuning fork and the wire. The frequency of the fork is Show Answer

Q166) A weight of 5 kg is required to produce the fundamental frequency of a sonometer wire. What weight is required to produce its octave? Show Answer

Q167) A vibrating sonometer wire is in resonance with a tuning fork of frequency 150 Hz. If only one loop is formed on the wire and the length of one loop is 40 cm, then the velocity of transverse waves on the wire will be Show Answer

Q168) What is the velocity of transverse waves travelling along a thin copper wire of length 50 cm and mass 1 gram, if it is stretched by a weight of 4 kg? Show Answer

Q169) A stretched wire of length 1 m and weighing 1 gram is in unison with a tuning fork of frequency 200 Hz. The tension in the wire will be Show Answer

Q170) Standing waves are produced in a stretched string of length 8 m. If the string vibrates in 4 loops and the wave velocity is 20 m/s, then the frequency of the string will be Show Answer

Q171) A string is stretched between two fixed points separated by 75 cm. It has two consecutive resonant frequencies of 420 Hz and 315 Hz. What is the lowest resonant frequency for the string? Show Answer

Q172) If a string fixed at both ends, vibrates in its fourth harmonic, the wavelength is 15 cm. What is the length of the string? Show Answer

Q173) If the sonometer experiment is performed in a lift and if the lift starts falling down freely, then the fundamental frequency of the sonometer wire will Show Answer

Q174) If the vibrating length of a string is increased by 25%, then its fundamental frequency will Show Answer

Q175) Two wires of the same material and same cross sectional area are vibrating with the same frequency. The first wire of length 80 cm is loaded with 8 kg and the second wire is loaded with 2 kg. The length of the second wire is Show Answer

Q176) The fundamental frequency of a sonometer wire is 100 Hz. If a weight of 3 kg is added to the hanger, the frequency of the wire is doubled. What was the initial load on the hanger? [The weight of the hanger is included in the load.] Show Answer

Q177) A string of length L between the two bridges of sonometer wire vibrates in the second harmonic. Its amplitude of vibration is maximum at Show Answer

Q178) A tuning fork of frequency 400 Hz, produces 10 beats/ sec, when sounded with a vibrating sonometer string. What must have been the frequency of the string if a slight increase in tensions in the string, produces fewer beats per second than before? Show Answer

Q179) A pulse of a wave train travels along a stretched string and reaches the fixed end of the string. It will be reflected back with Show Answer

Q180) A vibrating string fixed at both the ends is producing its seventh harmonic. How many nodes and antinodes are formed? Show Answer

Q181) The fundamental frequency of a sonometer wire is 200 Hz. It is found that a tuning fork of frequency 400 Hz produces resonant vibrations in the same wire. Then the wire vibrates with Show Answer

Q182) A sonometer wire is in unison with a tuning fork. When its length increases by 4%, it gives 8 beats/s with the same fork. What is the frequency of the fork? Show Answer

Q183) A string is kept stretched under a tension T, the velocity of transverse wave travelling along the string is Show Answer

Q184) A sonometer wire is vibrating in its second overtone. The number of nodes and antinodes formed is Show Answer

Q185) A stretched wire having tension 225 N produces six beats per second when it is tuned with a fork. When the tension changes to 256 N and it is tuned with the same fork, the number of beats remains unchanged. The frequency of the fork will be Show Answer

Q186) A sonometer wire is resonating with a tuning fork of frequency N. If its length is increased by 10%, by keeping the tension constant, 6 beats are heard per second, then Show Answer

Q187) A wire of mass 5 gram is kept stretched by a force of 400 N. When plucked at a point, transverse waves travel along the wire with a speed of 400 m/s. The length of the wire is Show Answer

Q188) If the weight attached to the sonometer wire is increased from 2 kg wt to 8 kg wt, the ratio of the number of antinodes observed in the second and first case will be Show Answer

Q189) The length and diameter of a metal wire is doubled. The fundamental frequency of vibration will change from 'n' to (Tension being kept constant) Show Answer

Q190) A tuning fork produces 4 beats/sec, with a sonometer wire of length 40 cm. It is found that when the length is increased to 44 cm, by keeping other factors constant, again 4 beats/sec are produced. What is the frequency of the tuning fork? Show Answer

Q191) A second harmonic is to be generated in a string of length L stretched between two rigid supports. The points at which the string has to be plucked and touched are Show Answer

Q192) The length of a sonometer wire is 1m. Where should be the bridge placed to divide the wire into 2 segments, whose fundamental frequencies are in the ratio 1:2? Show Answer

Q193) The frequency of a vibrating wire is n. If its tension is doubled, density is halved and the diameter is doubled then the new frequency will be Show Answer

Q194) The length of a string tied between two rigid supports is 50 cm. The maximum wavelength of a stationary wave produced on it is Show Answer

Q195) The successive resonating frequencies for a stretched wire are 250 Hz and 300 Hz. The wire is stretched between two rigid supports with a tension of 36 N.
If the mass per unit length of the wire is 0.01 kg/m, then the length of the wire is Show Answer

Q196) A tuning fork of known frequency 256 Hz produces 5 beats/s with a vibrating string of a piano. The beat frequency decreases to 2 beats/s when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was Show Answer

Q197) A string of mass 0.250 kg is under a tension of 2 N. The. length of the stretched string is 2 m, A transverse wave disturbance starts at one end of the string. How long will the disturbance take to reach the other end? Show Answer

Q198) A tuning fork is set vibrating along with a sonometer wire. 6 beats per second are produced when the length of the wire is either 20 cm or 21 cm. What is the frequency of the tuning fork? Show Answer

Q199) The fundamental frequency of a sonometer wire is 100 Hz for a certain length and tension. If only the length of the wire is increased by 25%, what will be the percentage change in the frequencies of second harmonics in the first and second case? Show Answer

Q200) A stretched wire of length 1 m has a mass of 0.5 g. The tension in the string is 20 N. It is plucked at a distance of 25 cm from one end. What is the frequency of vibration of the wire? Show Answer

Q201) A metal wire of linear mass density of 9.8 g/m is stretched with a tension of 10 kg-wt between two rigid supports 1 metre apart. The wire passes at its middle point between the poles of a permanent magnet, and it vibrates in resonance when carrying an alternating current of frequency n. What is the frequency n of the alternating source? Show Answer

Q202) Beats are heard when the A strings of two violins X and Y are played. If the tension in the A string of X is slowly increased, the beat frequency is decreased. This suggests Show Answer

Q203) Two wires are producing fundamental notes of the same frequency. Change in which of the following factors of one wire, will not produce beats between them? Show Answer

Q204) At the poles, a stretched wire of a certain length vibrates in unison with a tuning fork of given frequency. Then at the equator, for the same setting, for producing resonance with the same tuning fork, the vibrating length of the wire Show Answer

Q205) If the tension in a sonometer wire is increased by 69% then to keep the frequency constant, the length should be increased by Show Answer

Q206) . A 20 cm long string having a mass of 1.0 g is fixed at both the ends. The tension in the string is 0.5 N. The string is set into vibrations using an external vibrator of frequency 100 Hz. What is the separation (in cm) between the successive nodes on the string? Show Answer

Q207) The extension in a string obeying Hooke's law, is x. The speed of the wave in the stretched string is v. If the extension in the string is increased to 1.5 x, the speed of the wave in the string will be Show Answer

Q208) . A sonometer wire resonates with a given tuning fork forming standing waves with five antinodes between the two bridges when a mass of 9 kg is suspended from the wire. When this mass is replaced by a mass M, the wire resonates with the same tuning fork forming three antinodes for the same positions of the bridges. What is the value of M? Show Answer

Q209) A vibrating string of certain length L under a tension T resonates with a mode corresponding to the first overtone (third harmonic) of an air column of length 75 cm inside a tube closed at one end. The string also produces 4 beats per second when excited along with a tuning fork of frequency n. Now when the tension of the string is slightly increased, the number of beats reduces to 2 per second. The velocity of sound in air to be 340 m/s. What is the frequency n of the tuning fork? Show Answer

Q210) A hollow pipe of length 0.8 m is closed at one end. At its open end a 0.5 m long uniform string is vibrating in its second harmonic and it resonates with the fundamental frequency of the pipe. If the tension in the wire is 50 N and the speed of sound is 320 m/s, the mass of the string is Show Answer

Q211) In a sonometer experiment, the bridges are separated by a fixed distance. The wire which is slightly elastic, emits a note of frequency 'n' when held by tension 'T'. If the tension is increased to '4T', the note emitted by the wire will be of frequency Show Answer

Q212) A tuning fork vibrating with a sonometer wire of length 20 cm produces 5 beats per second. The beat frequency does not change if the length of the wire is changed to 21 cm. What is the frequency of the tuning fork (in Hertz)? Show Answer

Q213) The frequency of a streteched uniform wire of length L under tension is in resonance with the fundamental frequency of a closed pipe of the same length. If the tension in the wire is increased by 8 N, it is in resonance with the first overtone of the same closed pipe. What is the initial tension in the wire? Show Answer

Q214) Two uniform strings A and B made of the same metal are made to vibrate under the same tension. If the first overtone of A is equal to the second overtone of B and if the radius of A is twice that of B, the ratio of the lengths of the strings is Show Answer

Q215) A stretched wire emits a fundamental note of 256 Hz. Keeping the stretching force constant and reducing the length of the wire by 10 cm, the frequency becomes 320 Hz. What is the original length of the wire? Show Answer

Q216) A string stretched by tension T and of length L vibrates with fundamental frequency n. The tension in the stretched string is increased by 69% and the length of the string is reduced by 35%. Then the frequency of the vibrating string is Show Answer

Q217) If the speed of sound in air is 350 m/s, then the fundamental frequency of an open pipe 50 cm long will be Show Answer

Q218) If the speed of sound in air is v, then the shortest length of a pipe closed at one end which resonates for a frequency n is Show Answer

Q219) The frequency of the fundamental note produced by a pipe closed at one end is 100 Hz. Which one of the following frequencies will not be emitted by the pipe? Show Answer

Q220) Two consecutive harmonics of an air column in a pipe closed at one end are of frequencies 150 Hz and 250 Hz. What is the fundamental frequency? Show Answer

Q221) If the length of a closed organ pipe is 1 m and the velocity of sound is 330 m/s, then the frequency of the first overtone will be Show Answer

Q222) Two closed pipes produce 10 beats per second when emitting their fundamental notes. If their lengths are in the ratio of 25:26 their fundamental frequencies in Hz are: Show Answer

Q223) The air in a pipe closed at one end is in resonance with a vibrating tuning fork of frequency 170 Hz. If the velocity of sound in air is 340 m/s, the length of the vibrating air column is Show Answer

Q224) A tube closed at one end produces a fundamental note of frequency 480 Hz. If the same tube is kept open at both the ends, the fundamental frequency that can be excited is Show Answer

Q225) A pipe closed at one end and open at the other resonates with sound of frequencies 135 Hz and 165 Hz but not at any other frequency intermediate between the two. Then the frequency of the fundamental note of the pipe is Show Answer

Q226) The fundamental frequency of a pipe closed at one end is 20 Hz. What is the ratio of the frequencies of the third and fifth overtones? Show Answer

Q227) For a certain organ pipe, three successive resonance frequencies are observed at 400 Hz, 560 Hz and 720 Hz. The fundamental frequency of the pipe is Show Answer

Q228) The ratio of the fundamental frequencies of a closed pipe and an open pipe of the same length is Show Answer

Q229) The velocity of sound in a pipe of length 30 cm and open at both ends, in 330 m/s. If the frequency of the wave is 1100 Hz, which harmonic is emitted by the pipe? Show Answer

Q230) The velocity of sound in air is 320 m/s. The maximum length of an organ pipe closed at one end that can produce just an audible sound is Show Answer

Q231) Why is the sound produced by an organ pipe open at both ends is better than that of an organ pipe closed at one end? Show Answer

Q232) If the fifth overtone of a closed pipe is in unison with the fifth overtone of an open pipe, then the ratio of the length of closed pipe to open pipe will be Show Answer

Q233) A tuning fork of frequency 480 Hz is in unison with the first overtone of a pipe closed at one end. What is the fundamental frequency of the closed pipe? Show Answer

Q234) If the end correction of an open organ pipe is 0.8 cm, then the inner radius of the pipe will be Show Answer

Q235) The value of end correction for an open organ pipe of radius r is ______. Show Answer

Q236) A closed organ pipe and an open organ pipe have their first overtones identical in frequency. Their lengths are in the ratio Show Answer

Q237) Two organ pipes, closed at one end, when sounded together produce 3 beats/second. If their lengths are in the ratio of 101: 100, then the fundamental notes produced by them have the frequencies (in Hz) Show Answer

Q238) An air column in a pipe, which is closed at one end, will be in resonance with a tuning fork of frequency 200 Hz, if the length of the air column is
[velocity of sound in air = 320 m/s] Show Answer

Q239) What should be the length of a closed pipe to produce resonance with sound waves of wavelength 62 cm? Show Answer

Q240) The length of a pipe closed at one end is 33 cm and the speed of sound in air is 330 m/s. What is the frequency of the third overtone produced by the pipe? Show Answer

Q241) What is the effect on the fundamental frequency (v) of a closed organ pipe, if instead of air it is filled with a gas heavier than air? Show Answer

Q242) Two open organ pipes A and B have the same length but their diameters are 5 cm and 3 cm respectively. Then the fundamental frequencies are related as Show Answer

Q243) A tuning fork of frequency 256 Hz produces 5 beats/sec with a vibrating piano string. When the tension in the piano string is slightly increased, the number of beats decreases to 2 beats/sec. What was the original frequency of the piano string? Show Answer

Q244) You are given an open pipe of length one metre. Which resonant harmonic will be produced, with a tuning fork of frequency 480 Hz? (Velocity of sound = 320 m/s) Show Answer

Q245) The difference between the frequencies of the second and third overtones of an air column in a pipe closed at one end is 160 Hz. What is the frequency of its first overtone? Show Answer

Q246) A pipe of length 10 cm, closed at one end, has a frequency equal to half the 2nd overtone of another pipe open both the ends. What is the length of the open pipe? Show Answer

Q247) An organ pipe has a fundamental frequency of 100 Hz. Its second overtone is 500 Hz. What is the nature of the pipe? Show Answer

Q248) If the length of an open pipe is kept constant but the diameter of the pipe is increased, then its frequency will Show Answer

Q249) In an open organ pipe the fundamental frequency is 30 Hz. If the organ pipe is closed at one end, then the fundamental frequency will be Show Answer

Q250) The velocity of sound in air is 320 m/s. A pipe closed at one end has a length of 1 m. The air column in the pipe cannot resonate for sound of frequency
[Neglect the end correction] Show Answer

Q251) A pipe 20 cm long is closed at one end. Which harmonic mode of the pipe is resonantly excited by a source of 1237.5 Hz? (Sound velocity in air = 330 m/s) Show Answer

Q252) The number of possible natural oscillations of air column, in a pipe closed at one end, of length 85 cm whose frequencies lie below 1250 Hz are (velocity of sound = 340 m/s Show Answer

Q253) The fundamental frequency of a closed organ pipe of length 20 cm is equal to the second overtone of an organ pipe open at both the ends. The length of organ pipe open at both the ends is Show Answer

Q254) A 30 cm long pipe is open at both ends. Which harmonic mode of the pipe is resonantly excited by a 1.65 KHz source? [Speed of sound in air = 330 m/s] Show Answer

Q255) The third harmonic of an open pipe is in resonance with a tuning fork of frequency 495 Hz. What is the length of the open pipe if the velocity of sound in air is 330 m/s? (neglect the end correction) Show Answer

Q256) An open pipe of length L is emitting its fundamental frequency. If one end of the pipe is closed, then the frequency of the first overtone of the closed pipe is found to be higher by 100 Hz than the fundamental frequency of the open pipe. What is the fundamental frequency of the closed pipe? Show Answer

Q257) A and B are two metal tubes having equal lengths and equal inner diameters. For the tube A, both ends are open while for the tube B, one end is closed. What is the ratio of the fundamental frequencies of A and B? Show Answer

Q258) An open pipe is suddenly closed at one end with the result that the frequency of the third harmonic of the closed pipe is found to be higher by 100 Hz than the fundamental frequency of the open pipe. What is the fundamental frequency of the open pipe? Show Answer

Q259) An open organ pipe of length L vibrates in its fundamental mode. The pressure variation is maximum Show Answer

Q260) In the fundamental mode, the time taken by the sound wave to reach upto the closed end of a pipe, filled with air is 0.01 s. The fundamental frequency of vibration of air column is Show Answer

Q261) For a certain organ pipe, three successive resonant frequencies are observed at 300 Hz, 420 Hz and 540 Hz. The speed of sound in air is 340 m/s. The pipe is a Show Answer

Q262) An open pipe of length 120 cm vibrates in its fundamental mode. At what distance from one end of the pipe, the pressure variation is maximum? Show Answer

Q263) A steel rod of length 1 m is clamped at its centre. The fundamental frequency of longitudinal vibrations produced in the rod is 2.5 KHz. What is the speed of sound in steel? Show Answer

Q264) A cylindrical tube, open at both ends, has a fundamental frequency, fin air. The tube is dipped vertically in water so that half of it is in water. The fundamental frequency of the air-column is now Show Answer

Q265) Two open organ pipes of lengths 25 cm and 25.5 produce 10 beats/sec. What is the velocity of sound? Show Answer

Q266) The fundamental frequency of a closed pipe is 220 Hz. If (1/4) th of the pipe is filled with water, what will be the frequency of the first overtone of the pipe now? Show Answer

Q267) Which one of the following characteristics must remain constant for undamped oscillations of a particle? Show Answer

Q268) In the case of forced oscillations, if the oscillations are sustained in the body, then the amplitude of oscillations Show Answer

Q269) In tuning of a radio receiver, we use the phenomenon of Show Answer

Q270) If instead of water, the resonance tube is filled with a liquid of density higher than that of water, then the resonating frequency Show Answer

Q271) In a resonance tube experiment, a tuning fork resonates with an air column of length 12 cm and again resonates when it is 38 cm long. The end correction will be Show Answer

Q272) In a resonance tube experiment, the first and second resonance occur, when the water levels in the tube are 25 cm and 80 cms below the open end respectively. What is the inner diameter of the resonance tube? Show Answer

Q273) If a resonance tube gives two consecutive resonances at the length of 15 and 48 cm, then the velocity of sound in air is [frequency of fork = 500 Hz] Show Answer

Q274) An organ pipe (A) closed at one end and vibrating in its first harmonic and another pipe B open at both ends, vibrating in its third harmonic are in resonance with a given tuning fork. The ratio of the length of A to that of B is Show Answer

Q275) In the resonance tube experiment, maximum sound is heard, when the lengths of the resonating air columns are Show Answer

Q276) In a resonance tube experiment the difference between the first and second resonating lengths is 15 cm. Then the wavelength of the sound wave is Show Answer

Q277) A tuning fork is in unison with an air column of length 20 cm in a resonance tube experiment. If another identical resonance tube, whose length is more by 1 cm than the first tube is used, then 4 beats/second are heard with the same tuning fork. What is the frequency of the tuning fork? Show Answer

Q278) In a resonance tube experiment, the first resonance is obtained when the level of the water in the tube is at 20 cm from the open end. Resonance will also be obtained when the distance of the water level from the open end is Show Answer

Q279) The end correction of a resonance column in resonance tube experiment is 0.5 cm. If the shortest length resonating with a tuning fork is 16 cm, then the next resonating length will be Show Answer

Q280) In a resonance tube experiment the lengths of the air columns for the first and second resonance differ by 25 cm. What is the wavelength of the sound in the tube? Show Answer

Q281) For a resonance tube, the air columns for the first and second resonance differ in length by 15.5 cm. The wave length of the sound wave is Show Answer

Q282) In a resonance tube, the first resonating length is 0.2 m and the second resonating length is 0.62 m from the open end. What is the inner diameter of the tube? Show Answer

Q283) In a resonance tube experiment to determine the speed of sound in air, a pipe of diameter 5 cm is used. The air column in the pipe resonates with a tuning fork of frequency 480 Hz, when the minimum length of the air column is 16 cm. What is the speed of sound in air at room temperature? Show Answer

Q284) In a resonance tube experiment, the length of the air column that resonates in the fundamental mode, with a tuning fork is 10 cm. When the length is changed to 35cm, the same tuning fork resonates with the first overtone.
The end correction is Show Answer

Q285) A tuning fork of frequency 340 Hz is kept vibrating above a measuring cylinder of height 100 cm. Water is slowly poured in the cylinder. What is the minimum height of water in the tube for which resonance will be obtained?
(Speed of sound in air = 340 m/s) Show Answer

Q286) The fundamental resonance frequency in a tube closed at one end is to be increased. This cannot be achieved by Show Answer

Q287) A student performed the resonance tube experiment by using a tuning fork of frequency 512 Hz. He obtained the first and second resonances at 30.7 cm and 63.2 cm respectively. What was the error in the measurement of the velocity of sound, if the actual speed of sound at the temperature of the experiment was 330 m/s? Show Answer

Q288) While measuring the speed of sound by performing a resonance column experiment, a student gets the first resonance condition at a column length of 18 cm during winter- Repeating the same experiment during summer, he measures the column length as x cm for the second resonance. Then Show Answer

Q289) An air column in a resonance tube of length 1.5 m resonates with a source of frequency 125 Hz, when the water level in it is at a certain height from the bottom of the tube. What is the height of water level corresponding to the fundamental frequency?
(Neglect the end correction and speed of sound in air is 330 m/s.) Show Answer

Q290) An air column in a pipe of length 1 m and closed at one end, will be in resonance with a vibrating tuning fork of frequency 250 Hz, if the length of the column is
[v = 330 m/s] Show Answer

Q291) An air column in a pipe, which is closed at one end will be in resonance with a vibrating tuning fork of frequency 264 Hz for various lengths. Which one of the following lengths is not possible? [v = 330 m/s] Show Answer

Q292) When an open pipe is closed from one end, the third overtone of the closed pipe is higher in frequency by 150 Hz than the second overtone of the open pipe. The fundamental frequency of the open end pipe will be Show Answer

Q293) Two uniform wires of the same material are vibrating under the same tension. If the first overtone of the first wire is equal to the second overtone of the second wire and radius of the first wire is twice the radius of the second wire then the ratio of the lengths of the first wire to second wire is Show Answer

Q294) In sonometer experiment, a string of length 'L' under tension vibrates in second overtone between two bridges. The amplitude of vibration is maximum at Show Answer