Electric Cells - Jamb Physics Past Questions and Answers

Question 6:

• JAMB 1991

The function of the system of granulated carbon mixed with manganese (IV) oxide in a Letanche cell is to

A. Increase the e.m.f. of the cell to 2.0V
B. Prevent local action in the cell
C. Prevent polarisation in the cell
D. Make the cell black and hence a good radiator

Question 7:

• JAMB 1992

Which of the following factors has no effect on the e.m.f. of a primary cell?

A. Temperature
B. Size of the cell
C. Nature of the plate
D. Nature of the electrolyte

Question 8:

• JAMB 1993

A simple cell with mercury-amalgamated zinc electrode prevents

A. Local actions
B. Polarization
C. Buckling
D. Degradation

Question 9:

• JAMB 1994

Which of the following has the lowest internal resistance when new?

A. Leclanche cell
B. Daniel cell
C. Accumulator
D. Torch battery

Question 10:

• JAMB 1998

Which of the following can be used to reduce local action in a Laclanche cell?

A. A carbon rod as the positive pole
B. Pure zinc as the negative pole
C. Potassium permanganate solution in contact with the positive pole
D. Common salt solution