string under a tension of 50.5 N is used to whirl a rock in a horizontal circle of radius 2.55 m at a speed of 20.3 m/s on a frictionless surface as shown in the figure below. As the string is pulled in, the speed of the rock increases. When the string is 1.00 m long and the speed of the rock is 49.5 m/s, the string breaks. What is the breaking strength, in newtons, of the string?