Question

An 8.00 g bullet is fired into a 160 g block that is initially at rest at the edge of a table of 1.00 m height. The bullet remains in the block, and after the impact the block lands d = 1.6 m from the bottom of the table. Determine the initial speed of the bullet.

Answer 1

start with the fall from 1 m.

horizontal distance=horizontalvelociyt*time

where h= 1/2 g t^2 or t= sqrt 2h/g=sqrt 2/9.8
which means horizontal velociity is 1.6/sqrt(2/9.8)

now, having the horizontal velocity, use the conservation of momentum

(M+m)*horizontalvelocity= massbullet*v
solve for v