A particle starts from the origin, goes along the X-axis to the point (20m, 0) and then returns along the same line to the point (-20m,0). Find the distance and displacement of the particle during the trip.

Explanation

The ball is dropped, so it start falling the top of the building with zero initial velocity `(v_(o)=0)`. The motion diagram is shown with the given information in the adjoining figure.
Using the first equation of the constant acceleration motion, we have
`v_(t)=v_(o)+at rarr v=0+10t=10t` ...(i)
`v'=0+10(t+0.5)=10t+5` ...(ii)
Using values of v and v' in following equation, we have
`x-x_(o)=((v_(o)+v)/2)t rarr` window height `((v+v')/2)xx0.5rArr t=0.35s`
(a) From equation (i), we have `v=10t=3.5 m//s`
(b) From following equation, we have `" " x-x_(o)=((v_(o)+v)/2)t rarr h=((0+v)/2)t=61.25` cm