A point mass \(m\) is moved in a vertical circle of radius \(r\) with the help of a string. The velocity of the mass is \(\sqrt{7gr} \) at the lowest point. The tension in the string at the lowest point is:
1. | \(6 \text{mg}\) | 2. | \(7 \text{mg}\) |
3. | \(8 \text{mg}\) | 4. | \( \text{mg}\) |