Answer:
3.28 m/s
Step-by-step explanation:
From the question,
Applying newtons ,
F = mv²/r........................ Equation 1
Where m = mass of the rock, v = speed, r = radius of the circle, F = Centriputal force.
But,
Centriputal force is equal to the weight of the rock
F = mg................. Equation 2
Equate equation 2 into equation 1
mg = mv²/r
Therefore,
v = √gr...................... Equaion 3
Given: r = 2.2/2 = 1.1 m
Constant: g = 9.8 m/s²
Substitute into equation 3
v = √(9.8×1.1)
v = √(10.78)
v = 3.28 m/s
Hence the minimum speed is 3.28 m/s