(a)[1]
Complete the equation for the kinetic energy of an object moving at speed $v$, and state what the other terms in the equation mean.
(b(i))[2]
Calculate the rise in the rock's internal energy.
(b(ii))[2]
Use your result from (b)(i) to find the minimum possible speed of the rock at the point it reaches the Earth.
(b(iii))[1]
Suggest one reason why the speed found in (b)(ii) is lower than the rock's actual speed on impact with the Earth.