Quantity of Heat - Jamb Physics Past Questions and Answers

Question 16:

• JAMB 1999

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

Question 17:

• JAMB 1999

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

Question 18:

• JAMB 2000

A metal of mass 0.5kg is heated to 100°C and then transferred to a well-lagged calorimeter of heat capacity 80JK^-1 containing water of heat capacity 420JK^-1 at 15°C. If the final steady temperature of the mixture is 25°C, find the specific heat capacity of the metal.

A. 877Jkg^-1K^-1
B. 286Jkg^-1K^-1
C. 133Jkg^-1K^-1
D. 92Jkg^-1K^-1

Question 19:

• JAMB 2002

The time rate of loss of heat by a body is proportional to the

A. Difference in temprature between the body and its surroundings
B. Temperature of its surroundings
C. Ratio of the temperature of the body to that of its surroundings
D. Temperature of the body

Question 20:

• JAMB 2003

A 2000W electric heater is used to heat a metal object of mass 5kg initially at 10oC. If a temperature rise of 30oC is obtained after 10min, the heat capacity of the material is

A. 6.0 x 10⁴J^oC^-1
B. 4.0 x 10⁴J^oC^-1
C. 1.2 x 10⁴J^oC^-1
D. 8.0 x 10⁴J^oC^-1