Finding the expression for momentum.

AI Thread Summary
To find the bullet's speed, vbullet, after it embeds into a block, consider the conservation of momentum principle. Initially, the bullet has momentum p = mv, while the block is at rest. Upon impact, the combined system's momentum must equal the initial momentum of the bullet. The friction force acting on the block as it slides a distance d can be expressed using the coefficient of kinetic friction, μk, which affects the deceleration of the block. The final expression for vbullet can be derived by equating the initial momentum to the momentum lost due to friction over distance d.
aracali
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Homework Statement


A bullet of mass m is fired into a block of mass M that is at rest. The block, with the bullet embedded, slides distance d across a horizontal surface. The coefficient of kinetic friction is μk.

Find an expression for the bullet's speed vbullet.
Express your answer in terms of the variables m, M, μk, d, and appropriate constants.

Homework Equations


p=mv

After that I have nothing.
 
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Think a bit further. Why did you write p=mv? what are p, m, v?
 
ehild said:
Think a bit further. Why did you write p=mv? what are p, m, v?
p= momentum
m=mass
v=velocity

I also forgot to include:
Faverage(Δt)=mΔv=Δp=J
 
You have two objects, the bullet and the block. Both have momentums. What happens with the momentums when you fire a bullet into a block and the bullet is embedded in the block?
 

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