Quantity of Heat - Jamb Physics Past Questions and Answers

Question 26:

• JAMB 2009

An electric heater rated 220v, 1000 w is immersed into a bucket full of water, calculate the mass of water if the temperature changes from 30°c to 100°c and the current flows for 300seconds.
[specific heat capacity of water = 4200 jkg^-1 K^-1]

A. 4.28 kg
B. 42.86 kg
C. 1.02 kg
D. 7.14 kg

Question 27:

• JAMB 2011

A block of aluminum is heated electrically by a 30 w heater if the temperature rises by 10°c in 5 minutes, the heat capacity of the aluminum is

A. 900 JK^-1
B. 90 JK^-1
C. 100 JK^-1
D. 200 JK^-1

Question 28:

• JAMB 2012

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 29:

• JAMB 2012

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 30:

• JAMB 2012

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