(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 0.05 kg bullet traveling at 200 m/s embeds into a 1.0 kg stationary wood block suspended by two light strings. Find the change in vertical height of the block.

2. Relevant equations

Wnc = 0 ?

mgho + .5mvo^2 = mghf + .5mfv^2

Wnc != 0 ?

.5mvf^2 + mghf - .5mvo^2 - mgho

3. The attempt at a solution

I really have no idea where to start. I'm not entirely sure if the work of the non conservative forces is equal to zero or not. I'm not even sure what I would put as the initial and final velocities ( 200 and 0 respectively??).

If it's Wnc = 0, then I did this:

.5 ( 1.05 ) ( 200^2) = (1.05) (9.8) hf

2100 = 10.29 hf

2100/10.29 = 204.1m = hf

But that seems like a rather high number

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Energy Problem Help

**Physics Forums | Science Articles, Homework Help, Discussion**