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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.

User Bhilstrom
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1 Answer

3 votes

Answer:


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

User Zan
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