Answer:
341 m/s
Explanation:
During the collision, the momentum of the system is conserved. After the collision, the system's initial kinetic energy is converted to gravitational potential energy.
Conservation of energy:
PE = KE
mgh = ½ mv²
v² = 2gh
v² = 2g (L − L cos θ)
Plug in values and solve.
v² = 2 (9.8) (1.57 − 1.57 cos 26°)
v = 1.765 m/s
Conservation of momentum:
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
The block's initial speed is zero, so u₂ = 0. After the collision, the bullet and block have the same speed, so v₁ = v₂ = v.
m₁u₁ = (m₁ + m₂) v
Plug in values and solve:
(0.0052) u₁ = (0.0052 + 1.0) (1.765)
u₁ = 341 m/s