A charge Q is at the centre of a semicircle of diameter AB. If work done in moving a charge q along the semicircle is W₁ and work done in moving the same charge q along the path ACB is W₂, then

As the electric field is a conservative field, the work done in moving a charge of 'q' will only depend on the initial and final positions of the charge.

In both the paths the initial and final positions are same, so W₁ = W₂ $\ne$ 0( since the path is not a closed loop)