A force F is required to keep a 5 kg mass moving round a cycle of radius 3.5 m at a speed of 7 ms−17\,\mathrm{ms^{-1}}7ms−1 . What is the speed, if the force is tripled?
4.0 ms−14.0\,\mathrm{ms^{-1}}4.0ms−1
6.6 ms−16.6\,\mathrm{ms^{-1}}6.6ms−1
12.1 ms−112.1\,\mathrm{ms^{-1}}12.1ms−1
21.0 ms−121.0\,\mathrm{ms^{-1}}21.0ms−1