Answer:
The maximum speed the stone can attain without breaking the string is 7.416 m/s
Step-by-step explanation:
Given;
mass of the stone, m = 0.600 kg
length of string, L = 0.600 m
maximum tension on the string, T = 55.0 N
Total force acting on the stone in horizontal direction is given as;
∑

This force corresponds to maximum tension on the string;

where;
m is the mass of the stone
is the maximum speed the stone can attain without breaking the string, which corresponds to maximum tension on the string.
r is radius of the circular path of the string

The maximum speed the stone can attain without breaking the string is 7.416 m/s