# Energy transfer question (Use PE=KE or SUVAT ?)

1. May 30, 2015

### CannonSLX

1. The problem statement, all variables and given/known data
Object falls from a tree which is 3m above the ground, what is its velocity when it hits the ground ?

2. Relevant equations
mgΔh=1/2mv2
or
s=vt-1/2at2

3. The attempt at a solution
Using the idea of PE=KE, as the masses cancel out I get an answer of V=7.66ms-1
However I thought that this question can also be done with a suvat equation, I use the same condition which is used for KE [That U=0].

When attempting with suvat I get an answer of 17.15ms-1 why is that ?

2. May 30, 2015

### Staff: Mentor

Hard to tell if you don't show your work!

3. May 30, 2015

### CannonSLX

Sorry, I just wanted to know if it was actually possible to be done using suvat ?

4. May 30, 2015

### Staff: Mentor

Sure. And the answer should be the same

5. May 30, 2015

### CannonSLX

I just tried it again and looked like I forgot how to use my calculator , but I did get the same.

Thanks for confirming anyways :)