An astronaut with a mass of 95 kg is floating in space. If the astronaut throws an object with a mass of 7 kg at a speed of 7/4 m/s, how much will his speed change by?

1 Answer
Jan 30, 2016

v_1=7.755ms^-1

Explanation:

This concept is an issue of conservation of momentum.
That is, m_1\vec{u_i}=m_1\vec{v_1}+m_2\vec{v_2}

We know that initially the man was at rest. So, u_i=0ms^-1
So that makes our equation, -m_1\vec{v_1}=m_2\vec{v_2}
Disregarding the vectors/directions, it becomes m_1*v_1=m_2*v_2

We have m_1=95kg, m_2=7kg and v_2=7/4ms^-1
Substituting all these into the equation, we get
95*v_1=7*7/4

Now you see why v_1 is soo dissuading to watch.