WAEC Physics Past Questions & Answers - Page 256

1,276.

A ray of light strikes a plane mirror at a glancing angle of 50o. Calculate the angle between the incident and reflected rays

A.

20o

B.

40o

C.

50o

D.

80o

E.

100o.

Correct answer is D

No explanation has been provided for this answer.

1,277.

In which of the following media would sound waves travel fastest?

A.

Kerosine

B.

Alcohol

C.

Water

D.

lron

E.

Air

Correct answer is D

No explanation has been provided for this answer.

1,278.

The main reason why rice cooks faster in a pressure cooker than in cooking pot is that

A.

less heat escapes from the cooker

B.

the vapour pressure in the cooker is constant

C.

the rice is not affected by the draught over the cooker

D.

the vapour pressure in the cooker decreases

E.

the boiling point of water in the cooker is raised.

Correct answer is E

No explanation has been provided for this answer.

1,279.

Water boils at a lower temperature when heated at the top of a mountain than at sea-level because at the top of the mountain 

A.

saturation vapour pressure of water is higher than at sea-level

B.

sun adds more heat to the water

C.

temperature is lower than at sea- level

D.

relative humidity of the atmosphere is lower

E.

pressure of the atmosphere is lower

Correct answer is E

No explanation has been provided for this answer.

1,280.

Cloud formation is the direct result of

A.

precipitation

B.

vaporization

C.

fusion

D.

sublimation

E.

condensation

Correct answer is B

No explanation has been provided for this answer.