Question

A car travels with a uniform acceleration and changes its speed from 54 km/h to 72 km/h in 10 seconds. Calculate: - (i) The acceleration of the car in m/s2 (ii) The distance travelled by the car during this time interval.

Answer 1

Given :
u = 54 kmph = 54000 m
v = 72 kmph = 72000m
t = 10 sec

(i) To find the acceleration ;
v = u+at
72000 = 54000 + a×10
a = 1800 m/sec^2

(ii) To find the distance travelled ;
s = ut+1/2×at^2
= 54000×10 + 1/2 ×1800×100
= 540000 + 90000
= 630000 m
= 630 km