A force (F) acting on a particle varies work done by a particle varies with the with the position x as shown in figure
.
Find the work done by by force in displacing the particle from .
(a) `x =-2m` to `x=0`
(b) `x=0` to `x =2m.`.

Answer

A

Explanation

(a) From x=-2 m to x=0, displacement of the particle is along positive x-direction while force acting on the particle is along negative `x`-direction Therefore, work don eis negative and given by the area under F-x graph with projevtion along x-axis.
`:. W = -(1)/(2)(2)(10) = -10J`
(b) From `x=0` to `x=2m`, displacement of particle and force acting on the particle both are along positive x-direction. Therefore, work done is positive and given by the area under F-x graph, or
`W=1/2(2)(10)=10 J`,