Derive an expression for the potential energy due to two-point charges separated by distance
r12 in an electric field.
Share
Derive an expression for the potential energy due to two-point charges separated by distance
r12 in an electric field.
Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Explanation:
Let, V(r1) and V(r2) be the electric potentials of the field E at the points having position vectors r1 and r2.
Work done in bringing q1 from infinity to r1 against the external field = q1V(r1)
Work done in bringing q2 from infinity to r2 against the external field= q2V(r2)
Work done on q2 against the force exterted by q1 = 1/4πεo.(q1q2/r12)
Here, r12 is the distance between q1 and q2.
So, the total potential energy of the system= The work done in assembling the two charges
U= q1V(r1)+q2V(r2)+1/4πεo.(q1q2/r12)