Question 866:

• JAMB 1997

Equal masses of copper and rubber are raised to the same temperature. After sometimes, the copper was observed to be at a lower temperature because

A. The specific heat capacity of copper is lower than that of rubber
B. Copper expands more than rubber
C. The specific heat capacity of rubber is lower than that of copper
D. Rubber expands more than copper

Question 867:

• JAMB 1997

Before starting a journey, the tyre pressure of a car was 3 x 10⁵Nm^-2 at 27^oC. At the end of the journey, the pressure rose to 4 x 10⁵Nm^-2. Calculate the temperature of the tyre after the journey, assuming the volume is constant

A. 400^oC
B. 300^oC
C. 273^oC
D. 127^oC

Question 868:

• JAMB 1997

What happens when a, certain quantity of pure ice is completely changed to water at 0oC?

A. Latent heat is absorbed, the mass remains constant, and the volume decreases
B. Latent heat is given out, the mass remains constant and the volume decreases
C. Latent heat is given out, the mass increases and the volume remains constant
D. Latent heat is absorbed, the mass decreases and the volume increases

Question 869:

• JAMB 1997

A heating coil rated at 100W is used to boil off 0.5kg of boiling water. The time taken to boil off the water is [specific latent heat of vaporization of water = 2.3 x 10⁶Jkg^-1]

A. 1.15 x 10⁹ s
B. 1.15 x 10⁷ s
C. 1.15 x 10⁵ s
D. 1.15 x 10⁴ s

Question 870:

• JAMB 1997

A mass of a liquid at 30^oC is mixed with a mass of the same liquid at 70^oC and the temperature of the mixture is 45^oC. Find the ratio of the mass of the cold liquid to the mass of the other liquid.

A. 3 : 5
B. 5 : 3
C. 3 : 7
D. 7 : 3