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

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

EMF is induced due to change in

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

A simple device that prevents the direction of current from changing is called.

• Commutator A
• Rotor B
• Armature C
• Detector D

The magnitude of motional emf is given by

• 
  A
• 
  B
• 
  C
• 
  D

A.C is converted into D.C by

• Dynamo A
• Rectifier B
• Motor C
• Transformer D

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

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

the core of transformer is laminated so reduce.

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

Energy density in an inductor is.

• Directly proportional to magnetic field A
• Directly proportional to square of magnetic field B
• Inversely proportional to magnetic field C
• Inversely proportional to square of magnetic field D

In a coil current change from 2 to 4 A in .05 s . If the average induced emf is 8 V then coefficient of self-inductance is:

• 0.2 henry A
• 0.1 henry B
• 0.8 henry C
• 0.04 henry D

Lenz's law presented in

• 1834 A
• 1934 B
• 1826 C
• 1836 D

The winding of the electromagnet in motor are usually called.

• Magnetic coils A
• Field coils B
• Electric coils C
• electric o electric coils D

• 
  A
• 
  B
• 
  C
• 
  D

split rings are used in

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

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

• 1931 A
• 1731 B
• 1842 C
• 1831 D

1 Henry =

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