Answer:
[tex]v_1=-8.19\ m/s[/tex]'
Explanation:
It is given that,
Mass of the plunger, [tex]m_1=1.25\ kg[/tex]
Mass of the bullet, [tex]m_2=0.0175\ kg[/tex]
Initially both plunger and the bullet are at rest, [tex]u_1=u_2=0[/tex]
Final speed of the bullet, [tex]v_2=585\ m/s[/tex]
Let [tex]v_1[/tex] is the final speed of the plunger. Using the conservation of momentum to find it. The equation is as follows :
[tex]m_1u_1+m_2u_2=m_1v_1+m_2v_2[/tex]
Since, [tex]u_1=u_2=0[/tex]
[tex]m_1v_1+m_2v_2=0[/tex]
[tex]v_1=-\dfrac{m_2v_2}{m_1}[/tex]
[tex]v_1=-\dfrac{0.0175\times 585}{1.25}[/tex]
[tex]v_1=-8.19\ m/s[/tex]
So, the recoil velocity of the plunger is 8.19 m/s. Hence, this is the required solution.