Question

it was once recorded that a car left skid marks which were 300m in length, assuming that the car skidded to stop with a constant acceleration of -4ms-² the speed of the car before it began to skid is
a) 40√6ms-¹
b) 40√5ms-¹
c) 20√6ms-¹
d) 30√5ms-¹​

Answer 1

Answer:

Correct answer is c

Explanation:

Use 2as = V² - u²

Answer 2

Answer:

c) 20√6m/s

Explanation:

Distance travelled = 300m

acceleration = -4m/s^2

final velocity = 0m/s

using 3rd equation of motion

=> 2as = v^2 - u^2

=> 2x(-4)x300 = -u^2 (v = 0)

=> √2400 = u

=> 20√6m/s = u

hope it help you