Question

Two protons are separated by a distance of 2.0x10-5 m. What is their electrical potential energy?

Answer 1

The electrical potential energy between two point charges is given by:

`V=k(qQ)/(r)`

where:

k is the electrical constant

q, Q are the point charges

r is the distance between them

Protons have the same electric charge which is:

`q=Q=+e=+1.6\cdot10^(-19)C`

Lets plug the information in the formula above:

`\begin{gathered} V=(9\cdot10^9)\cdot((1.6\cdot10^(-19))\cdot(1.6\cdot10^(-19)))/(2.0*10^(-5)) \\ V=11.52\cdot10^(9+(-38)-(-5)) \\ V=11.52\cdot10^(-24) \\ V\approx1.2\cdot10^(-23)V \end{gathered}`

So our fina answer is:

`V=1.2\cdot10^(-23)V`