### Physics Past Questions

11

A gas at a volume of V0 in a container at pressure P0 is compressed to one-fifth of its volume. What will be its pressure if the magnitude of its original temperature T is constant?

• A. P0/5
• B. 4P0/5
• C. P0
• D. 5P0
JAMB 1999
12
A piece of substance of specific head capacity 450JKg-1K-1 falls through a vertical distance of 20m from rest. Calculate the rise in temperature of the substance on hitting the ground when all its energies are converted into heat. [g = 10ms-2]
• A. 2/9°C
• B. 4/9°C
• C. 9/4°C
• D. 9/2°C
JAMB 1999
13
I. A liquid boils when its saturated vapour pressure is equal to the external pressure
II. Dissolved substances in pure water lead to increase in the boiling point.
III. When the external pressure is increased, the boiling point increases.
IV. Dissolved substances in pure water decrease the boiling point.

Which combination of the above are peculiarities of the boiling point of a liquid?
• A. I, II and III
• B. I, II, III and IV
• C. I, II and IV
• D. II, III and IV
JAMB 1999
14
The temperature gradient across a copper rod of thickness 0.02m, maintained at two temperature junctions of 20°C and 80°C respectively is
• A. 3.0 x 102Km-1
• B. 3.0 x 103Km-1
• C. 5.0 x 103Km-1
• D. 3.0 x 104Km-1
JAMB 1999
15
Calculate the mass of ice that would melt when 2kg of copper is quickly transferred from boiling water to a block of ice without heat loss;
Specific heat capacity of copper = 400JKg-1K-1
Latent heat of fusion of ice = 3.3 x 105JKg-1
• A. 8/33kg
• B. 33/80kg
• C. 80/33kg
• D. 33/8kg
JAMB 1999