Question

How is the work done by a force measured when (i) force is in direction of displacement , (ii) force is at an angle to the direction of displacement ?

Answer 1

$$\begin{gathered} CaseI:(Forceisinthedirectionofdisplacement) \\ Workdone,W=FS\cos \theta \\ Here, \\ Fisforce,Sisdisplacement,and\theta istheanglebetweenforceanddisplacement \\ AsForceisinthedirectionofdisplacement,\theta =0^o \\ So,W=FS\cos 0^o \\ =FS \\ CaseII:(Forceisatangletothedirectionofdisplacement) \\ Workdone,W=FS\cos \theta \\ Here, \\ Fisforce,Sisdisplacement,and\theta istheanglebetweenforceanddisplacement \end{gathered}$$