Jamb Physics 2014 Past Questions and Answers

Question 31:

• JAMB 2014

The maximum power transfer occur in a cell when the external resistance is

A. Twice the internal resistance of the cell
B. The same as the internal resistance of the cell
C. Greater than the internal resistance of the cell
D. Less than the internal resistance of the cell

Question 32:

• JAMB 2014

If a metal wire 4m long and cross-sectional area 0.8 mm² has a resistance of 60, find the resistivity of the wire

A. 5.3x10^-7
B. 3.0x10^-5
C. 1.2x10^-6
D. 3.2x10^-6

Question 33:

• JAMB 2014

A circuit has a resistance of 200Ω. The resistance of the circuit can be reduced to 120Ω when

A. A 300Ω resistor is connected to it in parallel
B. An 80Ω resistor is conneceted to it in series
C. A 150Ω resistor is connected to it in parallel
D. A 240Ω resistor is connected to it in series

Question 34:

• JAMB 2014

PHCN measures its electrical energy in

A. W
B. KWh
C. Wh
D. J

Question 35:

• JAMB 2014

What is the best method of demagnetizing a steel bar magnet?

A. Hammering
B. Heating it
C. Rough handling it
D. Solenoid method