- #1

LostShadow

- 12

- 0

## Homework Statement

3 equal point charges, each with charge 1.55 microColoumb, are placed at the vertices of an equilateral triangle whose sides are of length 0.100 m. What is the electric potential energy of the system? (Take as zero the potential energy of the three charges when they are infinitely far apart.)

## Homework Equations

Use = 8.85×10−12 F/m or the permittivity of free space.

## The Attempt at a Solution

The answer must be in J. I tried finding equivalences in joules. So far I got..

1 J = VC.

Okay, so we have microC.

But I don't have V..

V = J/C = J/FV = Nm/As = Nm/C.

## Homework Statement

The electron orbits the proton at a distance of 0.063 nm.

What is the electric potential of the proton at the position of the electron?

What is the electron's potential energy?

## Homework Equations

Well, electric potential of a point chage is 1/4(pi)(epsilon 0) * q/r

And the potential energy of a charged particle is qV.

## The Attempt at a Solution

For the electric potential energy, the answer must be in V for some reason. I have q.

For the electron's potential energy, the answer must be in joules.

Still can't find a correlation between V = J/C = J/FV = Nm/As = Nm/C. ;/

A joule = VC, but I still don't have V..

## Homework Statement

A thin spherical shell of radius R has total charge Q. What is the electric potential at the center of the shell?

## Homework Equations

I don't know what the electric potential energy at the center of a shell is. I know for a charged particle it is U = qV.

## The Attempt at a Solution

I'm assuming q is not Q. And I don't have a formula to do an attempt with. We were not given the radius of the shell either. The answer must be in terms of Q, R, and appropriate constants.

On my 4th question, is there anything that is infinite in this universe? Meaning, any places where infinity exists? From what I know, the only thing I can think of is a black hole, which has infinite density. I'm not 100% sure on that.

Thanks.