List two conditions which need to be satisfied for the work to be done on an object.

(N/A) For work to be done on an object,the following two conditions must be satisfied:
$(i)$ $A$ force must be applied to the object.
$(ii)$ The object must undergo a displacement in the direction of the force (or have a component of displacement in the direction of the force,i.e.,the angle $\theta$ between force and displacement must be such that $\cos \theta \neq 0$).