Practice Test

Q1) Choose the incorrect statement from the following regarding magnetic lines of field: Show Answer

Q2) Which of the following correctly describes the magnetic field near a long straight current carrying wire? Show Answer

Q3) For a current in a long straight solenoid N- and S-poles are created at the two ends. Among the following statement, the incorrect statement is: Show Answer

Q4) The strength of magnetic field inside a long current carrying straight solenoid is: Show Answer

Q5) Which of the following property of a proton can change while it moves freely in a magnetic field? (There may be more than one correct answer) Show Answer

Q6) A positively charged particle (alpha - particle projected towards west is deflected towards north by a magnetic field. The direction of magnetic field is Show Answer

Q7) The phenomenon of Electro -magnetic induction is: Show Answer

Q8) The essential difference between an AC generator and a DC generator is that: Show Answer

Q9) Choose the correct option:
A rectangular coil of copper wires is rotated in a magnetic field. The direction of the induced current changes once in each: Show Answer

Q10) Choose the incorrect statement: Show Answer

Q11) At the time of short circuit, the current in the circuit: Show Answer

Q12) The most important safety method used for protecting home appliances from short circuiting or overloading is: Show Answer

Q13) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): Two bar magnets attract when they are brought near to each other with the same people.
Reason (R): Unlike poles will attract each other. Show Answer

Q14) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): Magnetic field lines never intersect.
Reason (R): At a particular point magnetic field has only one direction. Show Answer

Q15) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): In Fleming's Left Hand Rule, the direction of magnetic field, force and current are mutually perpendicular.
Reason (R): Fleming's Left Hand Rule is applied to measure the induced current. Show Answer

Q16) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): An alpha particle placed in a magnetic field will not experience any force, if it moves in the magnetic field parallel to field lines.
Reason (R): The force is zero if current and field are in the same direction. Show Answer

Q17) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): Safety fuses are made up of materials having a low melting point.
Reason (R): Safety fuses should be resistant to electric current. Show Answer

Q18) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): Copper is used to make electric wires.
Reason (R): Copper has very low electrical resistance. Show Answer

Q19) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): When two bulbs are operated on same voltage supply, having power 60W and 100W then 100 W bulb has less resistance than 60W.
Reason (R): The power of the bulb is directly proportional to the square of the voltage. Show Answer

Q20) What type of energy conversion is observed in a linear solenoid? Show Answer

Q21) What will happen if a soft iron bar is placed inside the solenoid? Show Answer

Q22) The magnetic filed lines produced inside the solenoid are similar to that of ______. Show Answer

Q23) After analyzing the graph a student writes the following statements:
(A) The magnetic field produced by the solenoid is inversely proportional to the current,.
(B) The magnetic field produced by the solenoid is directly proportional to the current.
(C) The magnetic field produced by the solenoid is directly proportional to square of the current.
(D) The magnetic field produced by the solenoid is independent of the current.
Choose from the following which of the following would be the correct statements(s): Show Answer

Q24) From the graph deduce which of the following statements is correct? Show Answer

Q25) A momentary deflection is shown by the galvanometer, when: Show Answer

Q26) Which phenomenon is involved in it? Show Answer

Q27) In above phenomenon, the current is induced in another conductor, Show Answer

Q28) The rule which helps us to know direction of induced current. Show Answer

Q29) Flemings right hand rule explains: Show Answer

Q30) Why do the iron filings arrange themselves in a particular pattern? Show Answer

Q31) What do the lines along which the iron fillings align represent? Show Answer

Q32) What does the crowding of iron fillings at the end of the magnet indicate? Show Answer

Q33) The closer field lines indicate: Show Answer

Q34) What is SI unit of magnetic field: Show Answer

Q35) Which of the following is the property of magnetic field lines? Show Answer

Q36) Which of the following correctly describes the magnetic field near a long straight wire? Show Answer

Q37) Which of the following properties of a proton can change when it moves freely in a magnetic field? Show Answer

Q38) The strength of magnetic field inside a long current carrying straight solenoid is Show Answer

Q39) The direction of the induced electric current in a conductor, when placed in a varying magnetic field can be assessed by Show Answer

Q40) Assertion : The magnetic field is stronger at a point which is nearer to the conductor and goes on decreasing on moving away from the conductor.
Reason : The magnetic field B produced by a straight current carrying wire is inversely proportional to the distance from the wire. Show Answer

Q41) Assertion : A current carrying conductor experiences a force in a magnetic field.
Reason : The force acting on a current carrying conductor in a magnetic field is due to interaction between magnetic field produced by the conductor and external magnetic field. Show Answer

Q42) Assertion : If an electron, moving vertically from outer space, enters the earth's magnetic field, then it gets deflected towards west.
Reason : Electron has negative charge. Show Answer

Q43) Assertion : The magnetic field produced by a current carrying solenoid is independent of its length and cross-sectional area.
Reason : The magnetic field inside the solenoid has variable value. Show Answer

Q44) Assertion : Production of an electric current in a closed circuit by a changing electric field is called an induced current.
Reason : The direction of induced current is given by Fleming's right and rule. Show Answer

Q45) Choose the incorrect statement from the following regarding magnetic lines of field. Show Answer

Q46) The magnetic field at a distance r from a long wire carrying current / is 0.4 T. The value of magnetic field at a distance 2r is Show Answer

Q47) Which of the following is not the application of electric motor? Show Answer

Q48) Assertion : When current passes through a solenoid, then it tends to contract.
Reason : The current flowing through two parallel wires in the same direction gives rise to force of attraction on each other. Show Answer

Q49) Assertion : Galvanometer is used to measure polarity.
Reason : Galvanometer is an instrument which is used to detect current in any circuit. Show Answer

Q50) Assertion : A pump operated by electric motor starts pumping liquid.
Reason : Motor converts mechanical energy to electrical energy. Show Answer

Q51) Which of the following is the correct representation of uniform magnetic field? Show Answer

Q52) Four students A,B,C and D plotted the sketch of the patterns of magnetic field lines representing the magnetic field around a current carrying straight wire as shown. Whose sketch is correctly represented? Show Answer

Q53) What type of energy conversion is observed in a linear solenoid? Show Answer

Q54) What will happen, if a soft iron bar is placed inside the solenoid? Show Answer

Q55) The magnetic field lines produced inside the solenoid are similar to that of Show Answer

Q56) After analysing the graph, a student writes the following statements.
I. The magnetic field produced by the solenoid is inversely proportional to the current.
II. The magnetic field produced by the solenoid is directly proportional to the current.
III. The magnetic field produced by the solenoid is directly proportional to square of the current.
IV. The magnetic field produced by the solenoid is independent of the current.
Which of the following would be the correct statement (s). Show Answer

Q57) Which one of the following is true about electric motor? Show Answer

Q58) Commercial electric motors do not use Show Answer

Q59) From the graph, deduce which of the following statements is correct? Show Answer

Q60) The student is still testing on the feasibility of using metal strips in the model his observations are given below
1. As the current reverses is in the coil for every half turn, the coil rotates in one direction.
2. The speed of rotation of the motor is increased, if the value of current is increased.
3. The direction of force, acting on the coil is given by Fleming's left hand rule.
4. The coil continues its rotation in magnetic field even if there is no current in circuit.
The correct observations made by him are Show Answer

Q61) The direction of rotation of the coil, when viewed from the front by the student is Show Answer

Q62) Which of the following is the correct representation of magnetic field lines due to a bar magnet? Show Answer

Q63) Magnetic effect of current was discovered by Show Answer

Q64) Inside the magnet, the field lindes moves Show Answer

Q65) Relative strength of magnetic field at a point in the space surrounding the magnet is shown by the Show Answer

Q66) Which of the following statement is not correct about the magnetic field? Show Answer

Q67) By which instrument, the presence of magnetic field be determined? Show Answer

Q68) The pattern of the magnetic field produced by the straight current carrying conducting wire is Show Answer

Q69) The strength of magnetic field around a current carrying conductor is Show Answer

Q70) A current through a horizontal power line flows from south to north direction. The direction of magnetic field line 0.5m above it is Show Answer

Q71) The nature of magnetic field line passing through the centre of current carrying circular loop is Show Answer

Q72) The strength of each of magnet reduces to half when it cut along its length into the equal parts magnetic field strength of a solenoid.
Polarity of solenoid can be determined by Show Answer

Q73) The factors on which one magnetic filed strength produced by current carrying solenoids depends are Show Answer

Q74) A soft iron bar is introduced inside the current carrying solenoid. The magnetic filed inside the solenoid Show Answer

Q75) When current is parallel to magnetic field, then force experience by the current carrying conductor placed in uniform magnetic field is Show Answer

Q76) A positive charge is moving upwards in a magnetic field directed towards north. The particle will be deflected towards Show Answer

Q77) Which of the following factors affect the strength of force experience by a current carrying conduct in a uniform magnetic field? Show Answer

Q78) Direction of rotation of a coil in electric motor is determined by Show Answer

Q79) In electric motor, to make the coil rotating continuously in the same direction, current is reversed in the coil after every half rotation by a device called Show Answer

Q80) The condition for the praenomen of electromagnetic induction is that there must be a relative motion between Show Answer

Q81) The instrument that use to defect electric current in the circuit is known as Show Answer

Q82) WE can induce the current in a coil by Show Answer

Q83) A magnet is moved towards a coil (i) quickly (ii) slowly. The induced potential difference Show Answer

Q84) A.C. generator works on the principle of Show Answer

Q85) Fleming's left hand and Right hand rules are used in Show Answer

Q86) A D .C generator works on the principle of Show Answer

Q87) If the current values periodically from zero to a maximum value, back to zero and then reverse its direction, the current is Show Answer

Q88) Earth wire carries Show Answer

Q89) The main advantage of A.C power transmission over D.C power transmission over long distance is Show Answer

Q90) Which among of these are the main characteristics of fuse element? Show Answer

Q91) Overloading is due to Show Answer

Q92) To convert an AC generator into DC generator Show Answer

Q93) What should be the core of an electromagnet? Show Answer

Q94) Who has stated the Right hand Thumb Rule? Show Answer

Q95) What is that instrument which can detect the presence of electric current in a circuit? Show Answer

Q96) Which device produces the electric current? Show Answer

Q97) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): Only a change in magnetic field lines linked with coil will induces current in the coil.
Reason (R): The presence of large magnetic flux through the coil maintains a current in a closed circuit coil.
Show Answer

Q98) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): When the direction of velocity of moving charge is perpendicular to the magnetic field, it experience a maximum force.
Reason (R): Force on the moving charge does not depends on the direction magnetic field in which it moves.
Show Answer

Q99) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): Fuse is a safety device which is installed to prevent electrical circuits and possible fires.
Reason (R): Fuse consist of tin-plated copper wire having low melting point, which melts and breaks the circuit if the current exceeds a safe value.
Show Answer

Q100) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): Steel core is used as an electromagnet
Reason (R): Steel gets permanently magnetized when the current flows through the coil wound around.
Show Answer

Q101) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): It is fatal to touch a live electric wire as the person gets a severe electric shock. In some cases, electric shock can even kill a person.
Reason (R): The electric current passes through the body to the earth forming a circuit and burns the blood.
Show Answer

Q102) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): Strength of an electromagnet depends on the magnitude of current flowing through them.
Reason (R): Electromagnets are majority used for lifting heavy weights.
Show Answer

Q103) Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
Assertion (A): It is easier to bring North pole of a magnet to South pole of other magnet.
Reason (R): There is a force of attraction between unlike poles of magnet. Show Answer

Q104) By ending current through a coil wound round a rod one can magnetize it permanently. Show Answer

Q105) The rate of change in magnetic flux produces induced emf or potential. Show Answer

Q106) In ideal conditions, green colour insulation is given for live wire. Show Answer

Q107) Over-loading is caused by connecting many devices to one supply point. Show Answer

Q108) Potential of the earthed wire is zero. Show Answer

Q109) When a magnet is moved with its north polarity towards a coil placed in a closed circuit, then the nears face of the coil shows north polarity Show Answer

Q110) When a coil and magnet both are stationery an induced emf is setup across the coil. Show Answer