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

Unit of self inductance is

• Weber A
• Tesla B
• Henry C
• Farad D

If the coil is wound on iron core, the flux through it.

• Decreases A
• Becomes zero B
• Increases C
• Remains constant D

Efficiency of transformer does not affected by

• Input voltage A
• Core of transformer B
• Insulation between sheet C
• Resistance of coils D

Lenz's law deals with

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

Energy density of an inductor is:

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

the core of transformer is laminated so reduce.

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

• 
  A
• 
  B
• 
  C
• 
  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

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

Eddy current is produced when:

• A metal is light in varying magnetic field A
• A metal is kept in steady magnetic field B
• A circular coil is placed in a steady magnetic field C
• A current is passed through a circualr coil 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

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

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

Lenz's law presented in

• 1834 A
• 1934 B
• 1826 C
• 1836 D

SI unit of hennery which is.

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