Question: The direction of induced e.m.f. can be found by_____________?

• 1. Laplace’s law
• 2. Lenz’s law
• 3. Fleming’s right hand rule
• 4. Kirchhoff s voltage law

Question: An open coil has_____________?

• 1. zero resistance and inductance
• 2. infinite resistance and zero inductance
• 3. infinite resistance and normal inductance
• 4. zero resistance and high inductance

Question: The inductance of a coil will increase under all the following conditions except______________?

• 1. when more length for the same number of turns is provided
• 2. when the number of turns of the coil increase
• 3. when more area for each turn is provided
• 4. when permeability of the core increases

Question: As per Faraday’s laws of electromagnetic induction, an e.m.f. is induced in a conductor whenever it_______________?

• 1. lies perpendicular to the magnetic flux
• 2. lies in a magnetic field
• 3. cuts magnetic flux
• 4. moves parallel to the direction of the magnetic field

Question: In an iron cored coil the iron core is removed so that the coil becomes an air cored coil. The inductance of the coil will_____________?

• 1. increase
• 2. decrease
• 3. remain the same
• 4. initially increase and then decrease

Question: Both the number of turns and the core length of an inductive coil are doubled. Its self-inductance will be_____________?

• 1. unaffected
• 2. doubled
• 3. halved
• 4. quadrupled

Question: Higher the self-inductance of a coil_____________?

• 1. lesser its weber-turns
• 2. lower the e.m.f. induced
• 3. greater the flux produced by it
• 4. longer the delay in establishing steady current through it

Question: Which of the following circuit element stores energy in the electromagnetic field ?

• 1. Inductance
• 2. Condenser
• 3. Variable resistor
• 4. Resistance

Question: The current zero interruption, in oil and air blast circuit breakers, is achieved by____________?

• 1. lengthening of the gap
• 2. cooling and blast effect
• 3. both (A) and (B)
• 4. deionizing the oil with forced air

Question: The current zero interruption, in oil and air blast circuit breakers, is achieved by_______________?

• 1. lengthening of the gap
• 2. cooling and blast effect
• 3. both A and B
• 4. deionizing the oil with forced air