Bullet fired vertically into 1 kg ballistic pendulum at 1000 m/s

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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:)