Skidding Distance of a moving vehicle on asphalt gravel and grass

[Unknown2194]

I am recreating a car accident, an inelastic collision. The two vehicles after the collision have an initial velocity of 21.69m/s. They skid 6m across asphalt with coefficient of friction value of 0.72. They then pass through 0.5m of gravel with a coefficient of friction value of 0.4. Finally they continue through grass with a coefficient of friction value of 0.35 until they come to rest.

The two vehicles have a combined mass of 4,151kg.
Gravitational value is 9.81

I am required to discover how far the cars travel through the grass until they come to rest. All formulas and equations would be helpful.



u = √ 2 μ g s ?

 

[Delphi51]

Welcome to PF. You are required to show an attempt before we can give much help. It will be necessary to work out how much they slow down in each interval. Start with the asphalt. It is the force of friction that causes them to decelerate. You should be able to calculate the force, then the acceleration and finally the change in velocity.

Once you've done one interval, the next one (gravel) will be very similar.