After a computer is switched off, a 0.40 kg copper heat sink cools from 80 ∘C80\ ^\circ\mathrm{C}80 ∘C to 30 ∘C30\ ^\circ\mathrm{C}30 ∘C. The specific heat capacity of copper is 385 J kg−1 ∘C−1385\ \mathrm{J\,kg^{-1}\,{}^\circ C^{-1}}385 Jkg−1∘C−1.
What energy is released by the heat sink as it cools? Use ΔQ=mcΔθ\Delta Q=mc\Delta\thetaΔQ=mcΔθ.
12 320 J12\,320\ \mathrm{J}12320 J
4620 J4620\ \mathrm{J}4620 J
16 940 J16\,940\ \mathrm{J}16940 J
7700 J7700\ \mathrm{J}7700 J
110 exam-style questions on Edexcel GCSE Physics 14.2 Specific heat capacity and latent heat, covering 14.2.1 Heating, temperature and changes of state, 14.2.2 Specific heat capacity and specific latent heat, 14.2.3 Specific heat capacity calculation, 14.2.4 Specific latent heat calculation, and 14.2.5 Reducing energy transfer through thermal insulation. Each one has a worked solution and a mark scheme showing where the marks go.