Example 1 · difficulty 3/5
A small stone tied to a string is whirled in a vertical circle of radius 0.9 m so that it just completes the loop. Taking g = 10 m s⁻², the minimum speed of the stone at the highest point of the circle is
- A. 9 m s⁻¹
- B. 3 m s⁻¹
- C. 6.7 m s⁻¹
- D. 1.5 m s⁻¹