Bullet shot through stationary wooden block

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AI Thread Summary
The discussion revolves around calculating the average force exerted on a stationary wooden block when a bullet passes through it. The bullet has an initial speed of 280 m/s and exits at 190 m/s, with the block weighing 1.50 kg and measuring 0.012 m in length. The change in kinetic energy of the bullet is determined to be equal to the work done by the block. The user realizes that to find the average force, they can use the relationship between work and distance, applying the formula work/distance = force. This understanding leads to a clearer path for solving the problem.
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Homework Statement



So I have a block that has had a bullet shot through it at an initial speed of 280m/s. It is 0.03kg and after it leaves the block it is traveling at 190m/s. The block is a length of 0.012m and weighs 1.50kg. What is the average force exerted on the block?

Homework Equations


ek=0.5mv2
f=ma



The Attempt at a Solution


I have no idea what I'm doing. I found the first part of the question, which was the change in kinetic energy.
 
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As you said, you already did the first part of this problem, which is to find the change in kinetic energy (This isn't just a random question, you're going to need this for the second part).

The bullet leaves the block with less kinetic energy because of the work the block does. Since the bullet doesn't interact with anything else, then the change on it's kinetic energy has to be equal to the work done by the block.

Now, with this, you should be abble to easily determine the work excerted by the block and you know the width of the block. Getting the average force should be pretty straight forward from there.
 
Oh so you just use w/d= f? I think I got it.
 
Precisely :D
 
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