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

SI unit of hennery which is.

• VSA-1 A
• VS-1 A B
• VS-1A-1 C
• VSA D

Commutator was invented by:

• William bills A
• William Gates B
• William tells C
• William Sturgeon D

The direction of induced current is always so as to oppose the change which causes the current, this is the statement of

• Lenz's law A
• Faraday's law B
• Ampere's law C
• Coulomb's law D

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

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

In A.C. inductor behaves as

• Capacitor A
• Resistor B
• Commutator C
• Transistor 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

Which one is not present in A.C. generator.

• Armature A
• Magnet B
• Slip rings C
• Commutator D

The application of mutual induction is a.

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

If force in the direction of velocity of conductor,  then induced current is directed,

• Anti clockwise A
• Clock wise B
• At equilibrium C
• None of above D

The self induction emf is some times called.

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

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

When a motor is over loaded then the magnitude of back emf.

• Increases A
• Decreases B
• Remain constant C
• Zero 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

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 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 magnitude of motional emf is given by

• 
  A
• 
  B
• 
  C
• 
  D