Electromagnetic Induction - Jamb Physics Past Questions and Answers

Question 6:

• JAMB 1981

A closed coil of wire is placed near a magnet. The magnet lies along the axis of the coil. Under which of the following conditions would there be no current in the coil?

A. When the coil is moved toward the stationary magnet
B. When the coil is moved away from the stationary magnet
C. When the coil is held stationary but the magnet is moved towards the coil
D. When both the coil and the magnet are held stationary
E. When the coil is held stationary but the magnet is moved away from the cell

Question 7:

• JAMB 1985

On which of the following does the operation of a moving coil ammeter depend? i. Electromagnetic induction ii. Force on a carrying-current conductor iii. Magnetic effect of an electric current

A. I only
B. Ii only
C. Iii only
D. Ii and iii only
E. I,ii and iii

Question 8:

• JAMB 1985

A transformer has a primary coil with 500 turns and a secondary coil with 2500 turns. When the voltage input to the primary coil is 120V, the output is

A. 6000V
B. 600V
C. 240V
D. 60V
E. 24V

Question 9:

• JAMB 1988

Which of the following ammeters may be used to measure alternating currents? i. moving-coil ammeter ii. moving-iron ammeter iii. hot-wire ammeter

A. I and ii only
B. Ii and iii only
C. I and iii only
D. I, ii, and iii

Question 10:

• JAMB 1988

The principle of operation of an induction coil is based on

A. Ohm's law
B. Amphere's law
C. Faraday's law
D. Columbs law