Page 43 - FINAL DBS10012_HEAT TEMPERATURE 20102022 (2) (1)

1.8 SAMPLE QUESTION

Temperature & Heat

Sample 1

a. State and describe TWO (2) concepts of heat transfer.

(4 marks)
b. Three temperature scales that are commonly used are Fahrenheit,

Celcius, and Kelvin. Convert the following units of temperature:
i) 200 ° C to Kelvin

ii) 80 ° F to Kelvin (6 marks)
iii) 120 K to Fahrenheit

c. i) Calculate the quantity of heat required to raise the temperature of

5kg aluminum from 10 ° C to 80 ° C. Specify Heat Capacity of aluminum
is 900 J/kg°C. (4 marks)

ii) A 50 g of gold at temperature of 200 ° C was placed in a container
which contains 90 g of water. The equilibrium temperature of the
mixture is 40 ° C. Calculate the initial temperature of the water before it (5 marks)

is mixed with gold. (Specific Heat Capacity of gold is 129 J/kg°C).

iii) 450 g of vegetable oil at a temperature of 60 ° C is poured into an

well-insulated beaker. Another 870 g of vegetable oil at 90 ° C is mixed
and stirred well inside the beaker. Calculate the final temperature of (6 marks)

the mixture if there is no interchange of heat from outside.

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