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

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

Energy stored in inductor is.

• 1/2 L I² A
• 1/2 LI B
• 1/2 L2I C
• 1/2 L2I2 D

Step up transformer is used.

• Step up D.C. voltage A
• Step up A.C. voltage B
• Step up both A.C and D.C. C
• Step up A.C. current D

Lenz's law is a consequence of the law of conservation of

• Charge A
• Momentum B
• Energy C
• Angular momentum D

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

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

• 
  A
• 
  B
• 
  C
• 
  D

Energy stored in an inductor is:

• 1/2L²I A
• 1/2L²/I B
• _1/2LI² C
• 1/2LI D

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

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

Electromagnetic induction obeys law of conservation

• Charge A
• Energy B
• Momentum C
• Mass 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 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

split rings are used in

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

When motor is just started, back emf is almost.

• Maximum A
• Zero B
• Minimum C
• Infinite D

For step down transformer

• Ns>Np A
• Np > Ns B
• Ns = Np C
• Ns > > > Np 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

If 10 A current passes through 100 mH inductor, then energy stored is.

• 100 J A
• 5 J B
• 20 J 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