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hi folks, last problem I can't get done here. I usually have a good idea of where to start, what to use. but I'm a bit flummoxed.

A neutron, of mass m = 1.67 10-27 kg, is localized inside a carbon nucleus, of radius 7.0 fm (1 fm 10-15 m). Use the uncertainty relations to calculate a minimum (negative) potential energy for neutrons inside heavy nuclei.

(deltax)*(delta p_x) > h-bar = h/(2*Pi), the uncertainty inequality

i'm not sure how to calculate the potential energy of a particle.

I have an equation for the kinetic energy of a particle, K=p^2/(2*m), in terms of the momentum and mass.

the textbook gives an example of potential energy of a spring, but this problem doesn't involve springs soo...

could the other uncertainty inequality be used here? I refer to

(delta E) * (delta t) > h-bar

I'm not sure if this energy would be potential, kinetic, or total energy. and I also don't know how to involve time, so I could get rid of the delta t.

any tips would be great. my approach to write down all relevant equations and then try to piece them together with the given constants has not worked this time.

Thanks much,

Yroyathon

## Homework Statement

A neutron, of mass m = 1.67 10-27 kg, is localized inside a carbon nucleus, of radius 7.0 fm (1 fm 10-15 m). Use the uncertainty relations to calculate a minimum (negative) potential energy for neutrons inside heavy nuclei.

## Homework Equations

(deltax)*(delta p_x) > h-bar = h/(2*Pi), the uncertainty inequality

## The Attempt at a Solution

i'm not sure how to calculate the potential energy of a particle.

I have an equation for the kinetic energy of a particle, K=p^2/(2*m), in terms of the momentum and mass.

the textbook gives an example of potential energy of a spring, but this problem doesn't involve springs soo...

could the other uncertainty inequality be used here? I refer to

(delta E) * (delta t) > h-bar

I'm not sure if this energy would be potential, kinetic, or total energy. and I also don't know how to involve time, so I could get rid of the delta t.

any tips would be great. my approach to write down all relevant equations and then try to piece them together with the given constants has not worked this time.

Thanks much,

Yroyathon

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