Particle potential energy - acceleration?

[reminiscent]

Homework Statement

Homework Equations

ΔU = U_f - U_i

The Attempt at a Solution

Would I have to make the left side of the equation equal to m*a*x? Is the x on the left side equal to -100 m?

 

[gneill]

What's the formal relationship between force and potential energy?

 

[reminiscent]

What's the formal relationship between force and potential energy?

The derivative of potential energy equals force (F_x = -dU/dx). So the derivative would turn it to be: -C/(x²). Then it's just plugging in from there, correct?

 

[reminiscent]

What's the formal relationship between force and potential energy?

For the acceleration, I got -0.0011 m/s^2. Does that seem too small?

 

[gneill]

For the acceleration, I got -0.0011 m/s^2. Does that seem too small?

The magnitude looks good but its sign is suspect. Check the details of your derivative.

 

[reminiscent]

The magnitude looks good but its sign is suspect. Check the details of your derivative.

Why isn't it negative, though? Since Fx = -dU/dx, wouldn't it be Fx = -(-C*-1*x^-2)? It will still be negative.

 

[gneill]

Why isn't it negative, though? Since Fx = -dU/dx, wouldn't it be Fx = -(-C*-1*x^-2)? It will still be negative.

Oops. You're quite right. My mistake.