Question

A string 1.0 m long breaks when it's tension is 100 N. What is the greatest speed at which it can be used to whirl a 1.0 kg stone? (neglect the gravitational pull of the earth on the stone)

Answer 1

Speed ​​can be counted in many ways, depending on the values ​​we know, so that we can calculate the speed.  Here we have a known value for tension 100 N. We also have a weight of 1kg stone whose speed we want to calculate. In this case we will use the formula for tension T = mg + ma, where we will ignore mg the expression due to the fact that we reject the influence of earth's gravity, so that we get the expression T = ma. From this expression we will extract the acceleration value and move it to the left side of the formula:

a = T/m,  a - acceleration (m/s²), T - tension (N, kgm/s²),  m - weight (kg), the length of the string is one meter.

a = 100(kgm/s²) / 1(kg) = 100 m/s² and the velocity is v = √a = √100 = 10 m/s.

Answer 2

V = √Tension / √mass/length

V = √100 / 1/1

V = √100

V = 10 m/s