Solving a Momentum Problem: Bullet-Block System with Spring Compression

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To determine the bullet's velocity at impact with the block, the discussion emphasizes analyzing the problem in two parts: the collision and the subsequent spring compression. The conservation of momentum applies during the collision, while the energy stored in the spring is relevant after the collision. The force exerted on the spring can be calculated using F = kx, but the key is to relate the kinetic energy of the bullet-block system to the potential energy stored in the spring. By understanding these conservation principles, one can derive the bullet's initial velocity. The approach focuses on energy and momentum conservation to solve the momentum problem effectively.
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A 11.0-g bullet is fired horizontally into a 108 g wooden block that is initially at rest on a frictionless horizontal surface and connected to a spring of constant 154 N/m. If the bullet-block system compresses the spring by a maximum of 76.0 cm, what was the velocity of the bullet at impact with the block.

what i did first was i set F=kx to find the force the bullet block system applied to the spring.

after solving for F, i couldn't find a way to relate force to the momentum equation
m1v1i=(m1+m2)vf
 
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mohamud3917 said:
what i did first was i set F=kx to find the force the bullet block system applied to the spring.
Instead of worrying about the force, consider the energy stored in the spring.
 
ok so how do i set it up
 
Think of the problem as having two parts:
(1) The collision itself. What's conserved during the collision?
(2) The compression of the spring after the collision. What's conserved here?
 
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