Answer to Question #121690 in Physics for Kelsey Latimer

Question

You tie a 5.8 kg mass to the end of a 88 cm long string. You then swing the mass a horizontal circle above your head until the string breaks. If you know the string can withstand a maximum tension of 1,503 N without breaking, what was the linear speed (in m/s) of the mass when the string broke?

Answer 1

The string breaks when the tension becomes higher than the allowable. The tension is caused by the centrifugal force:

$$T=\frac{mv^2}{R},\\\space\\ v=\sqrt{\frac{TR}{m}}=\sqrt{\frac{1.503\cdot0.88}{5.8}}=0.48\text{ m/s}.$$