Jamb Physics 1997 Past Questions and Answers

Question 36:

• JAMB 1997

What is the total electrical energy consumed by using an electric cooker rated 1000W for 5 hrs?

A. 5.3 x 10³J
B. 6.5 X 10³J
C. 1.8 X 10⁷J
D. 2.3 X 10⁷J

Question 37:

• JAMB 1997

The power dissipated in an a.c. circuit with an r.m.s, current of 5A, r.m.s voltage of 10V and a phase angle of 60^o is

A. 25W
B. 50W
C. 120W
D. 125W

Question 38:

• JAMB 1997

The voltage of the domestic electric supply is represented by the equation V = 311 sin314.2t. Determine the frequency of the a.c. supply [\(\pi\) = 3.142]

A. 50.0Hz
B. 100.0Hz
C. 311.0Hz
D. 314.2Hz

Question 39:

• JAMB 1997

In a purely inductive circuit, the current

A. Lags behind the voltage in phase by 90^o
B. Leads the voltage in phase by 90^o
C. Is in the same phase with the voltage
D. Leads the voltage by 180^o

Question 40:

• JAMB 1997

One of the features of the fission process is that

A. Its products are not radioactive
B. It leads to chain reaction
C. Neutrons are not released
D. The sum of the masses of the reactants equals the sum of masses of the products