1. The problem statement, all variables and given/known data A coin of mass 10g is dropped from the top of a tall building. If after failing for 10s , it falls intosoil and penetrates to a depth of 5cm, calculate (Q) the average force exerted on the coin by the soil. 2. Relevant equations 3. The attempt at a solution Should I use F=ma ? or use F= m( v-u ) / t ? to get the solution ? Give me hint !