Question

12. A car is travelling at 20 km/h, it speeds upto 60 km/h in 6 seconds. What is its acceleration?​

Answer 1

Thus, Acceleration, a = 1.85 m/s2.16-Sep-2020

Answer 2

• Initial velocity of car, u = 20 km/h = 20×5/18 m/s = 50/9 m/s

• Final velocity of car, v = 60 km/h = 60×5/18 m/s = 150/9 m/s

• time taken for change in velocity, t = 6 sec

• Let, acceleration = a

Using first equation of kinematics

v = u + a t

150/9 = 50/9 + a (6)

(150/9) - (50/9) = 6 a

100/9 = 6 a

a = 100/54

a = 1.851 m/s²