Answer:
[tex]v_2=8.85\times 10^{-4}\ m/s[/tex]
Explanation:
We have,
Mass of a wrench, m₁ = 4 g = 0.004 kg
Speed of wrench, v₁ = -15 m/s
Mass of the Astronaut, m₂ = 70 kg
It is required to find Astronaut's velocity. Let it is v₂. Using the conservation of linear momentum to find it.
[tex]m_1v_1=m_2v_2\\\\v_2=\dfrac{m_1v_1}{m_2}\\\\=\dfrac{0.004\times (-15)}{70}\\\\=-8.85\times 10^{-4}\ m/s[/tex]
So, his velocity is [tex]8.85\times 10^{-4}\ m/s[/tex].