Question

a car accelerates from rest to reach maximum velocity 20m/s at 5m/s² and then retards to rest at 2m/s². what is the time for which the car is in motion ?

Answer 1

Let v,t 1 ,t 2

be the maximum velocity attained, time for which car accelerated and the time for which car retarded respectively

⇒t 1

=(v−u)/a=(v−0)/2=v/2

⇒t

2 =(v−u)/a=(0−v)/(−4)=v/4

Now it is given that,

⇒t1+tt =3

⇒v/2+v/4=3⇒v=4m/s

I hope it's helpful

Answer 2

Answer:

4 m/s is the right answer hope it helped helped u mark me as brainliest