a car moves linearly with uniform retardation. If the car covers 40m in the last 2 seconds of its motion, what is the velocity of the car at the beginning of the last seconds? 

Asked by Omkarbswami | 22nd Mar, 2020, 06:40: PM

Expert Answer:

v2 - u2 = 2aS
0 - u2 = 2 (-a) 40
 
u2 = 80a
 
a = u2/80
 
Now, in the last second, t = 1 sec
retardation a = -u2/80 m/s2
 final velocity = 0
 
v = u + at
 = u - u2/80 ×1
 
u = 80 m/s

Answered by Shiwani Sawant | 23rd Mar, 2020, 02:13: PM