JAMB Physics Past Questions & Answers - Page 209

1,041.

Heat was supplied to a block of ice at 0oC until half of it melted. Which of the following statements is true?

A.

the temperature rises and the ice expand

B.

the temperature remains constant and the volume of the ice decreases

C.

the ice gives out heat as it melts and the temperature decreases

D.

the mass remains constant and the temperature increases

E.

the temperature decreases because some heat is lost

Correct answer is B

No explanation has been provided for this answer.

1,042.

An example of a scalar quantity is

A.

velocity

B.

weight

C.

electric charge

D.

acceleration due to gravity

E.

momentum

Correct answer is C

No explanation has been provided for this answer.

1,043.

A cell of e.m.f 2V and internal resistance 1\(\Omega\) supplies a current of 0.5 amps to a resistance whose value is

A.

0.5\(\Omega\)

B.

1\(\Omega\)

C.

2\(\Omega\)

D.

2.5\(\Omega\)

E.

3\(\Omega\)

Correct answer is E

1 = \(\frac{E}{R + r}\)

\(\frac{2}{R + 1}\) = 0.5

0.5R = 2 - 0.5 = 1.5

R = \(\frac{1.5}{0.5}\)

= 3\(\Omega\)

1,044.

Which of the following is NOT an effect that can be produced by an electric current?

A.

heat

B.

light

C.

sound

D.

motion

E.

none of the above

Correct answer is E

No explanation has been provided for this answer.