Question

A car travelling at 72 km/h decelerates uniformly at 2 m/s2 . Calculate the distance it travels during the third second.

Answer 1

Answer:

t= 10 seconds

distance in third second (s 3rd) = 15 m

Explanation:

u  initial  =72×  5/18  =20m/s

a =2m/s ^2

(a)s=ut+  1/2at^2

​v=u+at

v=0  

u−at=0  

20=2×1

t=10s

s=20×10−1/2 *2*100

s=100m

t=10s

$s_3$   =u+  a/2 (2n-1)

s  3rd =20−2/2  (2*3-1)

s  3rd  = 15m