A man whirls a stone of mass 250 gram, tied at the end of a string of length 2 m in a horizontal circle and at a height of 5 m from the ground. The string breaks and the stone flies off tangenitially and strikes the ground at a horizontal distance of 10 m from the man. What was the magnitude of the centripetal acceleration of the stone, when it was moving in the circle? (g = 10 m/s2)
50 m/s2
40 m/s2
30 m/s2
25 m/s2