Page 46 - FINAL DBS10012_HEAT TEMPERATURE 20102022 (2) (1)

Sample 5

a) State the definition and SI unit for the terms below:

i. Temperature [2 marks]

ii. Heat [2 marks]
iii. Specific Heat capacity [2 marks]

b) Describe two (2) characteristics of heat transfer process for:

i. Conduction [2 marks]
ii. Convection [2 marks]

iii. Radiation. [2 marks]

c) Calculate:

i. 1 kg sample of wood 40 kJ of heat is added, and its temperature is found to rise from

20⁰C to 44⁰C. What is the specific heat capacity of the wood? [3 marks]
ii. How much water at 50°C is needed to just melt 2.2 kg of ice at 0°C?
(Given specific latent heat of ice, L = 3.34 x 105 J/kg) [2 marks]

d) A 0.5kg of water at 60°C is mixed with m kg of water at 15 °C. The final temperature of the
mixture is 55 °C. (Specific heat capacity of water, c= 4200 Jkg-1°C-1).

i. Construct a table to compare Qhot and Qcold. [3 marks]

ii.Calculate the value of m [5 marks]

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