(Solved): The diagram below shows part of a downhill ski course which starts at point \( \mathrm{A}, 50 \mat ...

The diagram below shows part of a downhill ski course which starts at point \( \mathrm{A}, 50 \mathrm{~m} \) above level ground. Point \( B \) is \( 20 \mathrm{~m} \) above level ground. (a) A skier of mass \( 65 \mathrm{~kg} \) starts from rest at point \( A \) and during the ski course some of the gravitational potential energy transferred to kinetic energy. (i) From A to B, \( 24 \% \) of the gravitational potential energy transferred to kinetic energy. Show that the velocity at \( B \) is \( 12 \mathrm{~ms}^{-1} \). (ii) Some of the gravitational potential energy transferred into internal energy of the skis, slightly increasing their temperature. Distinguish between internal energy and temperature.