Answer:
u = 449 m/s
Explanation:
Given,
Mass of the bullet, m = 26 g
Mass of the wooden block,M = 4.7 Kg
height of the block,h = 0.31 m
initial speed of the block, u = ?
Using conservation of energy
[tex](M+ m)gh = \dfrac{1}{2}(M+m)v^2[/tex]
[tex]gh = \dfrac{1}{2}v^2[/tex]
[tex]v=\sqrt{2gh}[/tex]
[tex]v=\sqrt{2\times 9.81\times 0.31}[/tex]
v = 2.47 m/s
Now, using conservation of momentum to calculate the speed of the bullet.
m u + M u' = (M+m)v
m u = (M+m)v
0.026 x u = (4.7+0.026) x 2.47
u = 449 m/s
Hence, the speed of the bullet is equal to 449 m/s.
