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

The self induction emf is some times called.

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

Commutator was invented in

• 1834 A
• 1820 B
• 1840 C
• 1835 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

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 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 core of transformer is laminated so reduce.

• Magnetic loss A
• Hysteresis loss B
• Eddy current loss C
• Electric loss 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

When back emf in motor is zero, it draws.

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

The working principle of transformer is.

• Self induction A
• Faraday's law B
• Mutual induction C
• Electromagnetic induction 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

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

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

The device in which induced emf is statically induced emf is:

• Transforms A
• AC generator B
• Alevator C
• Dynamo D

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

The induced emf in a coil is proportional to:

• Magnetic flux through the coil A
• Rate of change of Magnetic flux through the coil B
• Area of the coil C
• Product of magnetic flux flux and area of the coil D

EMF is induced due to change in

• Charge A
• Current B
• Magnetic flux C
• Electric field D

If D.C. input for step up transformer, the output is

• Zero A
• High B
• Low C
• May be high or low D