Question

a 25gram bullet is fired upward through a .36kg block. the block goes up 17cm in the air and the bullet goes up 24m into the air. What is the initial velocity of the bullet?

Answer 1

assuming the loss of momentum of the bullet equals the gain of momentum of the block....

when the bullet leaves the block, it travels 24m
1/2 mv'^2=mgh h=24m
m is mass of bullet, M is mass block, v' is the velocity of bullet leaving the block. solve for v'

Now, the block.
1/2 Mv"=Mgh h=.17m
solve for the initial velocity of the block,v" after impact.

finally, loss of momentum bullet=momentum of block

mvi-mv'=Mv"
solve for vi