Answer to Question #183543 in Classical Mechanics for Jethro

Question

A bullet with a mass of 4 grams (g) is fired from a gun of mass 5kg with a velocity of 600m/s^-1 What is the velocity of recoil of the gun?

Answer 1

$\text{bullet mass and velocity}$

$m_b= 8*10^{-3}kg;V_{b1}= 600m/s;V_{b0}=0;$

$\text{gun mass and speed:}$

$m_g = 5 kg;V_{g1};V_{g0}=0;$

$\text{according to the law of conservation of momentum:}$

$m_b\Delta V_b+m_g\Delta V_g=0$

$\Delta V_g=-\frac{m_b\Delta V_b}{m_g}=-\frac{8*10^{-3}*600}{5}=-0.96m/s$

$V_{g1}= -0.96m/s$

$\text{}$ $\text{minus sign means that the direction of movement}\newline \text{ of the bullet and the gun are opposite}$

Answer:0.96 m/s velocity of recoil of the gun