Waec Physics 1991 Past Questions and Answers

Question 41:

• WAEC 1991

If the frequency of the e.m.f. source in the a.c. circuit illustrated above is \(\frac{500}{\pi}\)Hz. What is the reactance of the inductor?

A. 450
B. 0.9
C. 900
D. 567
E. 43

Question 42:

• WAEC 1991

Two objects of masses 80kg and 50kg are separated by a distance of 0.2m. If the gravitational constant is 6.6 x 10^-11Nm kg, calculate the gravitational attraction between them.

A. 4.9 x 10^-9N
B. 1.3 x 10^-6N
C. 6.6 x 10^-8N
D. 6.6 x 10^-6N
E. 2.6 x 10^-9N

Question 43:

• WAEC 1991

Two capacitors C₁ and C₂ are connected as shown in the diagram. The capacitance C₂ is twice C₁ when the key is opened the energy stored up in C₁ is W. If the key is later closed and the system is allowed to attain electrical equilibrium, the total energy stored in the system will be

A. \(\frac{1}{2}\)W
B. \(\frac{2}{3}\)W
C. W
D. 2w
E. 3W

Question 44:

• WAEC 1991

In which of the points labelled A, B, C, D and E on the conductor shown would electric charge tend to concentrate most?

A. A
B. B
C. C
D. D
E. E

Question 45:

• WAEC 1991

Which of the following is stored by dry Leclanche cell?

A. Chemical energy
B. Nuclear energy
C. Solar energy
D. Heat energy
E. Electrical energy