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

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' s1ast rule D

• 
  A
• 
  B
• 
  C
• 
  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

Efficiency of transformer does not affected by

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

Energy density of an inductor is:

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

If we make magnetic field stronger the value of induced current is.

• Decreased A
• Increased B
• Vanishes C
• Remain constant D

A metal rod of 1 m is moving at a speed of 1 ms-1 in a direction making an angle 30 ^o with 0.5 T magnetic field . The emf produced is.

• 0.25 N A
• 2.5 N B
• 0.25 V C
• 2.5 V D

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

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

Lenz's law presented in

• 1834 A
• 1934 B
• 1826 C
• 1836 D

Commutator was invented by:

• William bills A
• William Gates B
• William tells C
• William Sturgeon 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 self induction emf is some times called.

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

The jerks in D.C. motor are created by the use of.

• Armature A
• Commutators B
• Split rings C
• Source of emf D

split rings are used in

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