Given data
*The given mass of the bullet is m = 0.1 kg
*The given stationary mass is M = 9 kg
*The initial speed of the stationary mass is u_2 = 0 m/s
*The bullet bounces back with a speed is v_1 = 300 m/s
*The stationary mass moves off with a speed is v_2 = 8 m/s
The formula for the initial speed of the bullet is given by the conservation of momentum as
[tex]mu_1+Mu_2=mv_1+Mv_2[/tex]Substitute the known values in the above expression as
[tex]\begin{gathered} 0.1\times u_1+9\times0=0.1\times300+9\times8 \\ 0.1u_1=30+72_{}_{} \\ u_1=1020\text{ m/s} \end{gathered}[/tex]Hence, the initial speed of the bullet is u_1 = 1020 m/s
