# 1-D Kinematics Problem

1. Aug 2, 2012

### yjstudent

A California Condor is approaching its nest with a large chunk of carrion in its beak. As it approaches, it makes an upward swoop, achieving a momentary upward velocity of 12.8 m/s when the carrion falls from its mouth, hitting a cliff outcropping 32.1 m below. Determine the speed of the carrion upon hitting the outcropping.

This is a problem from Physics Classroom that I have to solve for AP Physics summer homework. I've never done physics before, so I'm finding it hard to even do basic problems.

I've tried setting v0=12.8, x=32.1, a=g=9.8 and plugging it into vf^2=v0^2+2ax.

Last edited: Aug 2, 2012
2. Aug 2, 2012

### voko

When the carrion is set loose, which way is it going? Up or down? How does gravity affect this?

3. Aug 2, 2012

### yjstudent

The carrion goes down. I think that gravity makes it go down faster?

4. Aug 2, 2012

### voko

No. Read the description. Just before the carrion is released the entire system bird + carrion is going UP.

First it will need to slow it to a (momentary) halt.

What does this all mean with regard to the signs of $v_0$ and $g$?

5. Aug 2, 2012

### yjstudent

Opposite signs? Since v0 goes up and g goes down

6. Aug 2, 2012

### voko

Exactly! Now you need to choose a positive direction - either up or down - and that should fix the signs for all the quantities (the distance, the velocity, and the acceleration), so you will be able to write down the equations.

7. Aug 2, 2012

### yjstudent

Yay thanks I got the answer..