Kinematics and One Dimensional Motion

[ayans2495]

Homework Statement

A car is travelling at 120 km/h, when the driver sees a herd of cows on the road ahead and slams on the brakes. The performance of the car’s brakes is such that the car comes to a stop in a distance D meters. Assuming that the acceleration of the car under braking is independent of the car’s speed, what distance would the car require to come to a stop if it were travelling at 40 km/h instead?

Relevant Equations

v=d/t, x=ut+1/2at^2

Would we assume that the deceleration of both instance are the same?

 

[hmmm27]

Would we assume that the deceleration of both instance are the same?

I think that's what the question is trying to say, by

Assuming that the acceleration of the car under braking is independent of the car’s speed,

 

[ayans2495]

I think that's what the question is trying to say, by

Don't worry, I've figured it out. It's D/9. Thank you though.

 

[hmmm27]

Don't worry, I've figured it out. It's D/9. Thank you though.

Not going to ; cheers.