A child of mass 5kg is going round a merry-go-round that makes 1...

The angular speed $\left(\omega\right)$ of the child can be calculated as follows:

$\begin{cases}\omega & = & \dfrac{2\pi}{3 . 14} \\ = & 2rad{s}^{- 1}\end{cases}$

The formula to calculate the centrifugal force on the child is given by

${F}_{r} = m{\omega}^{2}r . . . ( 1 )$

Substitute the values of the known parameters into equation (1) to calculate the required centrifugal force.

$\begin{cases}{F}_{r} & = & 5kg \times {\left(2rad{s}^{- 1}\right)}^{2} \times 2m \\ = & 40N\end{cases}$