Question

Why is electrostatic potential energy at infinity usually taken as zero?

Options

• Because potential energy must always be zero everywhere far away

• Because the electrostatic force becomes negligible at a very large distance

• Because the electrostatic force becomes maximum at a very large distance

• Because charges cannot exist at infinite separation

Answer 1

In electrostatics, potential energy at infinity is usually taken as zero because the force becomes negligible at a very large distance. Hence no work is needed to define a reference at infinity, making it a convenient zero of potential energy.