Question

A rock of mass m is twirled on a string in a horizontal plane. The work done by the tension in the string on the rock is..

Answer 1

work done by tension force on the twirled stone must be ZERO always

Step-by-step explanation:

As we know that work done by a force on an object is given as

`W = F.d`

`W = Fdcos\theta`

here we know that

`\theta` = angle between force and displacement

now we know that tension in the string and displacement of the object is always perpendicular to each other when the rock is twirled in circular path.

so we can say for this motion of the stone

`cos\theta = 0`

so work done by tension force on the twirled stone must be ZERO always