**Goal:** Hone the concept of potential energy functions

**Source:** UMPERG-ctqpe65

The

potential energy function for a certain body is shown at right. If the

body is released from rest at a location corresponding to point 4, the

object would …

- move towards larger values of x.
- move towards smaller values of x.
- remain stationary.
- oscillate back and forth.
- None of the above
- Cannot be determined

## Commentary:

## Answer

(2) At position 4 the object experiences a force toward the

origin given by the negative of the slope of the potential curve.

Frequently students interpret the fact that U is zero at point 4 to mean

that there is no force.