(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Astronaut is at rest in space. He has back of apples with him. How should he throw the rocks away to gain maxium velocity. (one by one, whole back, slice the apples into smaller fracments, group the apples, etc)

2. Relevant equations

p=mv

3. The attempt at a solution

I marked M_tot="total mass of apples"=n*m_app where m_app is mass of one apple and n the quantity of apples. When he throws the whole back (ignoring the mass of back) he gains velocity V_a=(M_tot*V)/(m_ast-M_tot) where V is the velocity he throws the back and m_ast is his mass. Now when he throws one by one he is at rest first so after throwing the momentum must be p_1=(m_ast-m_app)*V_ast1=m_appV, now when he throws second apple the momentum of system is P_1 so new momentum is P_2=(m_ast-2*m_app)V_ast2=2*m_app*V and continuing this way I get exact same velocity that I got at first since P_n=V_astn*(m_ast-M_tot)=m_tot*V.

But does it really go this easy way (I thought I needed to integrate something, but couldn,t get any equation for force), and am I thinking that velocity right. Now it is velocity relative to astronaut, should it be velocity relative to space?

Thanks for your help, and sorry my not-so-good english skills

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# Homework Help: Momentum of astronaut

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