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

the core of transformer is laminated so reduce.

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

The application of mutual induction is a.

• D.C. motor A
• Radio B
• Television C
• Transformer D

Energy density of an inductor is:

• UM=1/2μ_∘/B² A
• Um = 2μ_∘/B B
• UM = 1/2B²/μ_∘ C
• Um = 2B²/μ_∘ D

What is the co-efficient of mutual inductance, when the magnetic flux changes by 2 x 10^-2 Wb, and change in current is 0.01 A?

• 2 H A
• 3 H B
• 1/2 H C
• Zero D

The motional emf developed in a conduction depends upon.

• Length A
• Orientation B
• Magnetic field C
• All of the above 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' s1ast rule D

For step down transformer

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

Energy stored in inductor is.

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

When motor is just started, back emf is almost.

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

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

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

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

The current induced can be increased by:

• Using a stronger magnetic field A
• Moving the loop faster B
• Replacing the loop bay coi of many turns C
• All of above D

Self inductance of a long solenoid is given by

• 
  A
• 
  B
• 
  C
• None of the above D