(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A pellet gun fires a bullet into a stationary block of wood that is attached to a spring on a frictionless surface. When the bullet enters the wood, it reamins inside, and the bullet and block enter into simple harmonic motion with amplitude = 11cm. The bullet ( m = 5g) was initially travelling at 650 m/s before hitting the block of wood ( m = 2.5kg).

A: What is the spring constant of the spring?

B: What is the total energy of the system after the collision?(I know how to solve this one, I just need A to solve it.)

C: What is the maximum acceleration of the bullet/block system once it begins its oscillation?

D:Where will the bullet and block reach 0 velocity?(I think this is at the equilibrium position, but I'm not sure how to solve for it)

We know:

the amplitude of the block-and-bullet is .11m

the mass of the bullet is .005kg

the mass of the block is 2.5kg

the mass of the bullet-and-block is 2.505kg

the velocity of the bullet before it hits the block is 650 m/s.

2. Relevant equations

I know for B that you use the equation for total energy, kinetic energy + potential energy.

3. The attempt at a solution

My attempt at A; it wasn't so good. I tried using F = -kx, but that of course didn't work since we don't know the acceleration to solve for F. Then I considered kx=mg, but that doesn't work either because that only works for a spring that is suspended. So I'm not really sure where to go with this

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# Homework Help: Bullet-in-Block with Spring

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