WAEC Physics Past Questions & Answers - Page 76

376.

The temperature at which the water vapor in the air saturates the air and begins to condense is known as

A.

dew point

B.

critical point

C.

boiling point

D.

triple point

Correct answer is A

No explanation has been provided for this answer.

377.

Heat transfer by conduction is similar to wave motion because

A.

there is increase in temperature

B.

transfer of materials is involved

C.

charged particles vibrates at right angles

D.

no transfer of materials is involved

Correct answer is D

No explanation has been provided for this answer.

378.

A screw-jack has the distance between its successive threads as P and the length of its tommy bar as r. Its velocity ratio is given by the expression

A.

\(\frac{2 \pi r^2}{P}\)

B.

\(\frac{2 \pi r}{P}\)

C.

\(\frac{2 \pi}{rp}\)

D.

\(\frac{P}{2 \pi r}\)

Correct answer is B

No explanation has been provided for this answer.

379.

The S.I unit of power is

A.

N

B.

Pa

C.

W

D.

J

Correct answer is C

No explanation has been provided for this answer.

380.

A device that converts mechanical energy into electrical energy is

A.

a dynamo

B.

an electric motor

C.

an induction coil

D.

a transformer

Correct answer is A

No explanation has been provided for this answer.