Question

A 44 kg child jumps off a 2.2 kg skateboard that was moving at 8.0 m/s. The skateboard comes to a stop as a result. Find the speed at which the child jumped from the board. Show all your work. Assume a frictionless, closed system.

Answer 1

`v_f=8.4m/s`

Step-by-step explanation:

We need to use the conservation of momentum Law, the total momentum is the same before and after the kid leaves the skate.

In the axis X:

`(m_(kid)+m_(skate))*v_(o)=m_(kid)*v_f` (1)

`v_f=(m_(kid)+m_(skate))*v_(o)/m_(kid)=(44+2.2)*8/44=8.4m/s`