Ballistic Pendulum: Calculate Vf & Height

[lilkrazyrae]

a 4.00g bullet moving at 380m/s embeds itself in a wood block of mass 2996g suspended as a ballistic pendulum find: (a)the initial velocity of the block after the impact, and (b) how high the block rises.

I did it this way can someone tell me if i did it right
(a)m(1)v(1i) + m(2)v(2i) = (m(1) +m(2))v(f)
m(1)v(1i)/(m(1)+m(2))=v(f)
(4.00*380)/(4.00+2996)=.5067m/s

(b) U+K=U(2) +K(2)
1/2 mv^2 = mgh
v^2/2g=h
.507^2/(2*9.80)=.0131m

Any Help would be appreciated

 

[Andrew Mason]

a 4.00g bullet moving at 380m/s embeds itself in a wood block of mass 2996g suspended as a ballistic pendulum find: (a)the initial velocity of the block after the impact, and (b) how high the block rises.
I did it this way can someone tell me if i did it right
(a)m(1)v(1i) + m(2)v(2i) = (m(1) +m(2))v(f)
m(1)v(1i)/(m(1)+m(2))=v(f)
(4.00*380)/(4.00+2996)=.5067m/s
(b) U+K=U(2) +K(2)
1/2 mv^2 = mgh
v^2/2g=h
.507^2/(2*9.80)=.0131m
Any Help would be appreciated

Your method is correct. Your numbers look ok too.

AM