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

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

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

If the north pole of a magnet moves away from a metallic ring

• Clockwise A
• Anticlockwise B
• First clockwise and then anticlockwise C
• None of above D

Eddy current is produced when:

• A metal is light in varying magnetic field A
• A metal is kept in steady magnetic field B
• A circular coil is placed in a steady magnetic field C
• A current is passed through a circualr coil D

A metal rod of 1 m is moving at a speed of 1 ms-1 in a direction making an angle 30 ^o with 0.5 T magnetic field . The emf produced is.

• 0.25 N A
• 2.5 N B
• 0.25 V C
• 2.5 V D

The movement of conductor in magnetic field produces electrical current was discovered in:

• 1931 A
• 1731 B
• 1842 C
• 1831 D

The Si unit of Mutual inductance is:

• VA^-1S^-1 A
• VAS^-1 B
• VSA^-1 C
• ASV^-1 D

The unit of induced emf is

• Ampere A
• Volt B
• Joule/coulomb C
• Both (b) and (c) D

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

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

If magnetic field is doubled then magnetic energy density becomes.

• Four times A
• Two times B
• Three times C
• Six times 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

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

• 
  A
• 
  B
• 
  C
• 
  D

Output of D.C. motor is

• A.C. energy A
• Mechanical energy B
• Chemical energy C
• D.C. energy D

The illustration of the phenomenon of mutual induction is in the device of

• Transformer A
• Inductor B
• A.C. Generator C
• Ammeter 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

A step up transformer is used 120 V line to provide 240 V. If primary coil has 100 turns the number of turns is secondary is.

• 50 A
• 100 B
• 150 C
• 200 D

The negative sign with induced emf in Faraday's law is in accordance with

• Lenz's law A
• Amperes law B
• Boyle's law C
• Gauss law D