A man starts from his home at `8.00` am to his office. He walks with a speed of `2 ms^(-1)` on a road upto his office `3.0 km ` away from his hom. He stays in the office upto `4.00 pm` and returns to his home by which moves non-stop with a speed of `10 ms^(-1)`. Calculate
(i) the time taken by man to reach his office and
(ii) time taken by man to reach his home. Also plot `x-t` graph of his motion.

Explanation

(i) Speed of man `= 2m s^(-1) " " ` Distance travelled =3.0 km = 3000 m
`therefore " "` time taken ,` t= ( "Distance ")/( "speed ") =( 3000)/(2) =1500s =( 1500)/( 60) =25 `min.
So , that man reaches his office at 8.25 am
During his stay in the office from 8.25 am to 4.00 pm,no distance is travelled by him.
(ii) For return journey
Speed `= 10 ms^(-1) ` Distance =300 m ` " "therefore ` Time taken `" " = ( 300)/( 10 ) =300s `
` =( 300)/( 60 ) =` 5 min
So , the man reaches his home at 4.05 pm. Distance -time graph of his motion is shown in figure .