Will someone check my work to see if Im on the right track?

AI Thread Summary
The discussion centers on a collision and momentum problem involving a bullet and a ballistic pendulum. The user calculates the impulse given to the block and determines that it rises 5.1 meters after the collision. They clarify that the collision is inelastic, which is acceptable since they are not using energy conservation for the solution. Another participant confirms that the calculations appear correct, although they note that the explanation of how a ballistic pendulum works is not accurate. Overall, the user seems to be on the right track with their calculations.
camel-man
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This is collisions and momentum problem. for some reason it just seems like a short problem and I am use to doing long problems so I am here to check my work.

the questions is

A 50g bullet is fired vertically up at a 1.00 kg ballistic pendulum . The bullet strikes the block at
1000 m/s and emerges from it at 800 m/s. How far does the block rise? Assume that the
duration of the collision is instantaneous, in other words, during the collision no external forces
were acting on the system

my answer

Impulse given to block=0.050x1000-0.500x800=10=change in the block's momentum=1.00xv→v=10m/s. Using v²=u²+2as with v=0, u=10, a=-g=-9.8, we get 0=100-2x9.8s→s=5.1m.
[The collision isn't elastic but this doesn't matter since we aren't using energy conservation to solve the problem].

Am i missing something else?
 
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hi camel-man! :wink:
camel-man said:
Impulse given to block=0.050x1000-0.500x800=10=change in the block's momentum=1.00xv→v=10m/s. Using v²=u²+2as with v=0, u=10, a=-g=-9.8, we get 0=100-2x9.8s→s=5.1m.
[The collision isn't elastic but this doesn't matter since we aren't using energy conservation to solve the problem].

Am i missing something else?

looks ok to me :smile:

(though that's not how a ballistic pendulum works :confused:)
 
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