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Question
Calculate the amount of heat energy required to raise the temperature of 100 g of copper from 20°C to 70°C. specific heat capacity of copper = `390 J kg^-1 K^-1`.
Solution
Mass of copper m = 100 g = 0.1 kg
Change of temperature Δt = (70 − 20)°C
Specific heat of capacity of copper = `390 J kg^-1K^-1`
Amount of heat required to raise the temperature of 0.1 kg of copper is
Q = m × Δt × c
= 0.1 × 50 × 390
= 1950 J
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