Ohm's law - Jamb Physics Past Questions and Answers

Question 6:

• JAMB 1982

A high-resistance voltmeter reads 3.0V when connected across the terminals of a battery on open circuit and 2.6V when the battery supplies a current of 0.2A through a lamp. The resistance of lamp is

A. 2.00\(\Omega\)
B. 13.00\(\Omega\)
C. 0.52\(\Omega\)
D. 0.13\(\Omega\)
E. 1.50\(\Omega\)

Question 7:

• JAMB 1983

A 24V potential difference is applied across a parallel combination of four 6-ohms resistor, The current in each resistor is

A. 1A
B. 4A
C. 16A
D. 18A
E. 36A

Question 8:

• JAMB 1984

Two cells each of e.m.f. 1.5V and an internal resistance 2\(\Omega\) are connected in parallel. Calculate the current flowing when the cells are connected to a 1\(\Omega\) resistor

A. 0.75\(\Omega\)
B. 1.5\(\Omega\)
C. 0.5\(\Omega\)
D. 1.0\(\Omega\)
E. 0.6\(\Omega\)

Question 9:

• JAMB 1985

A cell gives a current of 0.15A through a resistance of 8\(\Omega\) and 0.3A. When the resistance is changed to 3\(\Omega\) the internal resistance of the cell is

A. 0.05\(\Omega\)
B. 1.00\(\Omega\)
C. 1.50\(\Omega\)
D. 2.00\(\Omega\)
E. 2.50\(\Omega\)

Question 10:

• JAMB 1985

An electric kettle, connected to a 240V mains, produces 6.0 x 10⁵J of heat energy to boil a quantity of water in 5 minutes. Find the resistance of the kettle.

A. 14.4\(\Omega\)
B. 28.8\(\Omega\)
C. 144\(\Omega\)
D. 288\(\Omega\)
E. 2880\(\Omega\)