Question

How much energy is lost by 20 kg copper if it is cooled from 50°C to 30°C?

Answer 1

The specific heat capacity of copper is 0.385 J/g^oC, which equals 385 J/kg^oC

$Q=cm\Delta{T}=385\frac{J}{kg\cdot{\degree{C}}}\times20kg\times(50\degree{C}-30\degree{C})=154000J=154kJ$

Answer: 154 kJ