Question

A car is moving with initial speed 20 m/ s^2 and accleration of 5m/ s^2 applied for some time distance travel by car 200 km find time taken by car​

Answer 1

Explanation:

Use the formula

S = ut+(1/2)at^2

S is displacement

u is initial velocity/speed

t is time and

a is acceleration.

Initial speed = 20 m/s

Acceleration = 5m/s^2

Distance = 200km = 200000 m

Now, s= ut+(1/2)at^2

200000= 20(t) +1/2(5)t^2

=> (5/2)t^2 + 20t = 200000

Take 5/2 common

=> (5/2)(t^2 + 8t) = 200000

=> t^2 +8t = 200000×2/5

=> t^2 +8t -80000 =0

=> t = ???