Answer:
The speed of the plank is 81.68 m/s
Explanation:
Given that,
Speed of bullet = 152 m/s
Speed of wood = 128 m/s
Speed of another bullet = 97 m/s
We need to calculate the speed of plank
Using conservation of momentum
[tex]m_{1}u_{1}=(m_{1}+m_{2})v[/tex]
Where,
u = initial velocity
v = final velocity
[tex]152m_{1}=(m_{1}+m_{2})128[/tex]....(I)
[tex]m_{1}97=(m_{1}+m_{2})v[/tex]....(II)
From equation(I) and equation(II)
[tex]\dfrac{152}{97}=\dfrac{128}{v}[/tex]
[tex]= \dfrac{128\times97}{152}[/tex]
[tex]v=81.68\ m/s[/tex]
Hence, The speed of the plank is 81.68 m/s
