# Potential Energy and Force

1. Oct 17, 2013

### gcharles_42

1. The problem statement, all variables and given/known data

A particle of mass m = 10 kg moves in space under the action of a conservative force. Its potential energy is given by
PE = 2xyz + 3z2 + 4yx + 16
where PE is in Joules and x, y, and z are in meters. Calculate the x-, y-, and z-components of the force on the particle when it is at the position x = 18 m, y = 13 m, and z = 19 m.

2. Relevant equations

F= - d/dx (PE)

3. The attempt at a solution

So far I took the partial derivatives in terms of x, y, and z but I don't know how to incorporate the object's weight. I feel like the weight is important since they mentioned it.
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Oct 17, 2013

### haruspex

There is no other reason to suppose the mass is relevant. The force (and hence the PE) may be unrelated to mass. Sometimes they throw in redundant info as an extra test of your understanding.