2nd Year Physics Chapter 15 Online MCQ Test for 12th Class Physics Chapter 15 (Electromagnetic Induction)

Unit of self inductance is

• Weber A
• Tesla B
• Henry C
• Farad D

Lenz's law was given by Heinrich lenz in:

• 1894 A
• 1904 B
• 1854 C
• 1834 D

Commutator was invented by:

• William bills A
• William Gates B
• William tells C
• William Sturgeon D

Mutual induction play role in.

• Generator A
• D.C. motor B
• Galvanometer C
• Transformer D

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

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

A.C. Generator based upon the

• Lenz's law A
• Maxwell's relation B
• Faradays law of electromagnet induction C
• Mutual induction 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

• 
  A
• 
  B
• 
  C
• 
  D

The only difference between the construction of D.C and A.C is.

• Carbon burshes A
• Coil B
• Commutator C
• Magnetic field D

Commentator was invented by

• Henry A
• Ousted B
• Maxwell C
• William sturgeon D

The current induced can be increased by:

• Using a stronger magnetic field A
• Moving the loop faster B
• Replacing the loop bay coi of many turns C
• All of above D

What is the co-efficient of mutual inductance, when the magnetic flux changes by 2 x 10^-2 Wb, and change in current is 0.01 A?

• 2 H A
• 3 H B
• 1/2 H C
• Zero D

In A.C. generator , when plane of coil is perpendicular to magnetic field, then output of generator is.

• NwAB A
• 2pi f B
• Maximum C
• Zero D

If speed of rotation of a generator is doubled the output voltage will be.

• Remain same A
• Double B
• Four time C
• One half D

The induction can be increased by winding the wire around a core made of.

• Copper A
• Silicon B
• Iron C
• Aluminum 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 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