Question

A car is running in a road with accelerating motion. It travels 10 m distance in 3rd second after the start and 12 m in 5 th second. Now what distance does it travel in 8 th second after its start ?

Answer 1

The car starts from rest therefore the initial speed u = 0. Nothing is said about the initial position and we therefore assume it is equal to 0. Hence the position x is given by the equation

x = (1/2) a t 2

where a is the acceleration (=8 m/s2) and t is the period of time between initial and final positions

x = (1/2)8 (10)2 = 400 m

b) The velocity v of the car at the end of the 10 seconds is given by

v = a t = 8 * 10 = 80 m/s