91Ó°ÊÓ

Work: Work is the product of the component of force in the displacement direction and the magnitude of the displacement.

Consider the given information:

By applying a force at an angle from the horizontal a boy pulls her sister to a distance of\(30.0{\rm{ m}}\)

The work done is given as,

\(W = Fd\cos \theta \)

Here,\(F\)is the magnitude of the force,\(d\)is the magnitude of displacement, and\(\theta \)is the angle between the force vector and the displacement vector.

Putting all known values,

\(\begin{aligned}{}W &= \left( {50.0{\rm{ N}}} \right) \times \left( {30.0{\rm{ m}}} \right) \times \cos \left( {30^\circ } \right)\\ &= 1299{\rm{ J}}\end{aligned}\)

Therefore, the required work is done by the boy pulling her sister is \(1299{\rm{ J}}\).