Electrostatics - Jamb Physics Past Questions and Answers

Question 16:

• JAMB 1989

The electrochemical equivalent of silver is 0.0012gC^-1. If 36.0g of silver is to be deposited by electrolysis on a surface by passing a steady current for 5.0mins, the current must be

A. 6000A
B. 100A
C. 10A
D. 1A

Question 17:

• JAMB 1990

Which of the following statements are true of an insulated charged body carrying positive charge? i. it contains excess positive charges. ii. it creates an electric field. iii. it possesses potential energy. iv. it carries electric current.

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

Question 18:

• JAMB 1990

The total energy required to send a unit positive charge round a complete electrical circuit is the

A. Kinetic energy
B. Potential difference
C. Electromotive force
D. Electrical energy

Question 19:

• JAMB 1991

An insulated rod when rubbed with a material acquires

A. A negative charge if it is made of glass and rubbed with silk
B. No charge if it is made of glass and rubbed with fur
C. No charge if it is made of copper and rubbed with silk
D. A positive charge if it is made of copper and rubbed with fur

Question 20:

• JAMB 1991

The electrochemical equivalent of platinum is 5.0 x 10^-7kgC^-1 to plate-out 1.0kg of platinum, a current of 100A must be passed through an appropriate vessel for

A. 5.6 hours
B. 56 hours
C. 1.4 x 10^{4 hours}
D. 2.0 x 10^{4 hours}