An object of mass 2 kg is taken to a height 5 m from the ground (g = 10 m `s^(-2)`).
What external force must act to bring the mass to that height?

Explanation

The external applied force `vec(F)_(a)` which takes the object to the height 5 m is `vec(F)_(a)=-vec(F)_(g)`
`" "vec(F)_(a)=-(-mghat(j))=mghat(j)`
where, `hat(j)` represents unit vector along vertical upward direction.