A charge q is placed at a distance 3R from the centre of a grounded conducting sphere of radius R. The image and its distance are respectively
1
\(-{q \over 3}\) and \(R \over 3\)
2
\(-{q \over 3}\) and \(R \over 6\)
3
- q and \(R \over 3\)
4
\(-{q \over 3}\) and \(R \over 3\)