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

When the back emf is zero, its draws.

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

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

• Copper A
• Silicon B
• Iron C
• Aluminum D

Lenz's law deals with

• Magnitude of emf A
• Direction emf B
• Direction of induced current C
• Resistance D

1 Henry =

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

When a coil is moved in a uniform magnetic field, an induced emf is produced due of change in

• Flux density A
• Electric flux B
• Magnetic flux C
• Magnetic field strength D

In D.C. generator, split rings act as.

• Capacitor A
• Commutator B
• Resistor C
• Inductor D

The Lenz's law fulfils.

• Law of conservation of energy A
• Law of conservation of charge B
• Law of conservation of momentum C
• Kirchhoff's law 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

One henry is equal to

• 1 ohm x 1 sec A
• 1 ohm x 1 hertz B
• 1 ohm x 1 metre C
• All of above D

the core of transformer is laminated so reduce.

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

When the back emf in a current is zero, it draws

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

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

The device in the circuit that consume electrical energy are known as.

• Dissipaters A
• Generator B
• Load C
• Motors D