Current Electricity - Jamb Physics Past Questions and Answers

Question 101:

• JAMB 2006

A cell of internal resistance r is connected to an external resistor R. The conductor for maximum power transfer is?

A. R < r
B. R = r
C. R = 2r
D. R > r

Question 102:

• JAMB 2006

A conductor has a diameter of 1.00 mm and length 2.00m. if the resistance of the material is 0.1Ω, its resistivity is?

A. 2.55 x 10⁵ Ωm
B. 2.55 x 10² Ωm
C. 3.93 x 10^-6 Ωm
D. 3.93 x 10^-8 Ωm

Question 103:

• JAMB 2007

Three cells each of e.m.f 1.5 V and internal resistance 2.5Ω are connected as shown in the diagram above. Find the net e.m.f and the internal resistance

A. 1.5V, 7.50Ω
B. 1,5V, 0.83Ω
C. 4.5V, 7.50Ω
D. 4.5V, 0.83Ω

Question 104:

• JAMB 2008

Find the effective resistance in the diagram above

A. 6 Ω
B. 12 Ω
C. 18 Ω
D. 24 Ω

Question 105:

• JAMB 2009

Calculate the e.m.f of the cell in the above circuit if its internal resistance is negligible

A. 12 V
B. 8 V
C. 2 V
D. 36 V