Question

A charge of \[2 \times 10^{-9}\ \text{C}\] is brought from infinity to a point P where the potential is \[4 \times 10^4\ \text{V}\]. The work done in bringing this charge is:

Options

• \[2 \times 10^{-5}\ \text{J}\]

• \[8 \times 10^{-6}\ \text{J}\]

• \[8 \times 10^{-5}\ \text{J}\]

• \[8 \times 10^{-4}\ \text{J}\]

Answer 1

The work done in bringing a charge \[q\] from infinity to a point at potential \[V\] is \[W = qV\]. Substituting, \[W = 2 \times 10^{-9} \times 4 \times 10^4 = 8 \times 10^{-5}\ \text{J}\].