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

The motional emf developed in a conduction depends upon.

• Length A
• Orientation B
• Magnetic field C
• All of the above D

In case of inductor , energy is stored in the

• Electric field A
• Magnetic field B
• Potential field C
• Gravitational field D

The motional emf depends upon the

• Length of conductor A
• Speed of conductor B
• Strength of magnet C
• All of these D

Which of the following quantities remain constant in step up transformer?

• Current A
• Voltage B
• Power C
• Heat D

Step up transfer has a transformation ratio of 3:2. What is the voltage in secondary , If voltage in primary is 30 V?

• 45 V A
• 15 V B
• 90 V C
• 300 V D

1 Henry =

• VSA^-1 A
• VS^-1A^-1 B
• V^-1SA C
• VSA^-2 D

If the coil is wound on iron core, the flux through it.

• Decreases A
• Becomes zero B
• Increases C
• Remains constant D

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

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

split rings are used in

• A.C. generator A
• A.C. motor B
• Transformer C
• D.C. motor D

• Lenz's law A
• Faraday's law B
• Ampere's law C
• None of these D

Output of D.C. motor is

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

The direction of induced current is always so as to oppose the change which causes the current is:

• Faraday's law A
• Lenz's  law B
• Ohm's law C
• Kirchhoff's 1st rule 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

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 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

A current generator device converts:

• Mechanical energy into chemical energy A
• Chemical energy into electrical energy B
• Mechanical energy into electrical energy C
• Both b and c D

If we make magnetic field stronger the value of induced current is.

• Decreased A
• Increased B
• Vanishes C
• Remain constant D