Question: Two coils have self-inductances of 10 H and 2 H, the mutual inductance being zero. If the two coils are connected in series, the total inductance will be_____________?

• 1. 6 H
• 2. 8 H
• 3. 12 H
• 4. 24 H

Question: Lenz’s law is a consequence of the law of conservation of__________?

• 1. induced current
• 2. charge
• 3. energy
• 4. induced e.m.f.

Question: In case all the flux from the current in coil 1 links with coil 2, the co-efficient of coupling will be____________?

• 1. 2.0
• 2. 1.0
• 3. 0.5
• 4. zero

Question: A 200 turn coil has an inductance of 12 mH. If the number of turns is increased to 400 turns, all other quantities (area, length etc.) remaining the same, the inductance will be___________?

• 1. 6 mH
• 2. 14 mH
• 3. 24 mH
• 4. 48 mH

Question: The self inductances of two coils are 8 mH and 18 mH. If the co-efficients of coupling is 0.5, the mutual inductance of the coils is______________?

• 1. 4 mH
• 2. 5 mH
• 3. 6 mH
• 4. 12 mH

Question: In case of an inductance, current is proportional to___________?

• 1. voltage across the inductance
• 2. magnetic field
• 3. both A and B
• 4. neither (A) nor (B)

Question: For a purely inductive circuit which of the following is true ?

• 1. Apparent power is zero
• 2. Relative power is.zero
• 3. Actual power of the circuit is zero
• 4. Any capacitance even if present in the circuit will not be charged

Question: An e.m.f. of 16 volts is induced in a coil of inductance 4H. The rate of change of current must be______________?

• 1. 64 A/s
• 2. 32 A/s
• 3. 16 A/s
• 4. 4 A/s

Question: Two coils have inductances of 8 mH and 18 mH and a co-efficient of coupling of 0.5. If the two coils are connected in series aiding, the total inductance will be______________?

• 1. 32 mH
• 2. 38 mH
• 3. 40 mH
• 4. 48 mH

Question: The core of a coil has a length of 200 mm. The inductance of coil is 6 mH. If the core length is doubled, all other quantities, remaining the same, the inductance will be_____________?

• 1. 3 mH
• 2. 12 mH
• 3. 24mH
• 4. 48mH