Question

The tension in a 2 m length of string that whirls a 1 kg mass at 4 m/s in a horizontal circle is calculated to be 8 N. How do you alculate the tension for the following case: twice the length of string?

Answer 1

The tension will be `4"N"`

Explanation:

The tension is equal to the centripetal force given by:

`F=(mv^2)/r`

You can see that doubling `r` will therefore half the tension to `4"N"`

Check:

`F=(1xx4^2)/4=4"N"`