Question

What will be the work done by electrons moving around the nucleus in an atom? Explain.

Answer 1

The work done is zero. The electrostatic force of attraction between the positively charged nucleus and the negatively charged electron acts radially inward (centripetal force). The displacement of the electron at any instant is tangential to its circular orbit. Because the force and displacement are perpendicular (θ = 90°), cos (90°) = 0, resulting in no mechanical work done.