WAEC Physics Past Questions & Answers - Page 246

1,228.

The heat capacity of a substance is the energy

A.

required to raise the temperature of a unit mass of the substance by one degree.

B.

required to raise the temperature of the substance by one degree

C.

absorbed by the substance at constant temperature

D.

lost by a unit mass of the substance.

Correct answer is B

No explanation has been provided for this answer.

1,229.

An iron rod of length 50m and at a temperature of 60oC is heated to 70oC. Calculate its new length. (Linear expansivity of iron = 1.2 x 10-5K-1)

A.

50.006m

B.

50.060m

C.

51.600m

D.

51.200m

Correct answer is A

No explanation has been provided for this answer.

1,230.

Iron at 30oC feels colder to the hand than wood at 28oC because

A.

their linear expansivities are not equal.

B.

the temperature of the iron is higher than that of the wood

C.

iron is a better radiator of heat than wood

D.

iron conducts heat more quickly from the hand than wood

Correct answer is D

No explanation has been provided for this answer.