(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A particle is trapped in a potential well described by U(x)= 1.8 x²-b where U is in joules, x is in meters, and b = 4.5 J.

Find the force on the particle when it's at x = 2.8m

Find the force on the particle when it's at x = 0 m

Find the force on the particle when it's at x = -1.4 m.

2. Relevant equations

F(x) = -dU(x) / dx

3. The attempt at a solution

so I just differentiated U(x), slapped a negative sign, and ended up with F(x) = 3.6x

Plugged in 2.8m, ended up with -10.08, and it ain't right. Any ideas why? I'm thinking itmighthave to do with the phrase "potential well".

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# Homework Help: Force from potential equation

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