Second Year Physics Chapter 15 Online MCQ Test for 2nd Year Physics Chapter 15 Electromagnetic Induction Preparation

Self induction does not depend on

• Number of turns of the coil A
• Area of cross section of the core B
• Nature of material of the core C
• Current through inductor D

When back emf in motor is zero, it draws.

• Zero current A
• Minimum current B
• Maximum current C
• Steady current D

DC generator by william Sturgeon in:

• 1894 A
• 1961 B
• 1834 C
• 1961 D

A real transformer does not change.

• Voltage level A
• Current level B
• Power level C
• Frequency D

• 
  A
• 
  B
• 
  C
• 
  D

Energy stored in an inductor is:

• 1/2L²I A
• 1/2L²/I B
• _1/2LI² C
• 1/2LI D

A 50 mH coil carries a current of 2.0 a , then energy stored in tis magnetic field is.

• 0.1 J A
• 10 J B
• 100 J C
• 1000 J D

Which one is not present in A.C. generator.

• Armature A
• Magnet B
• Slip rings C
• Commutator D

Induced emf in A.C. generator can be increased by

• Decreasing area of coil A
• Decreasing magnetic field B
• Increasing area of coil C
• Slowing down speed of coil D

If force in the direction of velocity of conductor,  then induced current is directed,

• Anti clockwise A
• Clock wise B
• At equilibrium C
• None of above D

The jerks in D.C. motor are created by the use of.

• Armature A
• Commutators B
• Split rings C
• Source of emf D

When motor is just started, back emf is almost.

• Maximum A
• Zero B
• Minimum C
• Infinite D

When a conductor moves across a magnetic field an emf is set up this emf is called.

• Variable emf A
• Constant emf B
• Back emf C
• Induced emf D

The emf induced by the motion of a conductor across a magnetic field is called:

• Motional emf A
• Rotational emf B
• Induced emf C
• All of above D

A simple device that prevents the direction of current from changing is called.

• Commutator A
• Rotor B
• Armature C
• Detector D

The rod of unit length is moving at 30 o through a magnetic field of 1 T. If the velocity of rod is 1 m/s, then induced emf in the rod will be given by

• I V A
• 0.25 V B
• 0.5 V C
• 0.6 V D

By winding the coil around a less magnetic core, self induction.

• Will increase A
• Will decrease B
• Remain same C
• First increase then decrease D