posted by Lindsay on .
A railroad flatcar is loaded with crates. The coefficient of static friction between the crates and the floor is 0.27. If the train is moving at 59.7 km/hr, in how short a distance can the train be stopped with a constant acceleration without causing the crates to slide?
I've tried this and I still can't get it. Can someone please show me the steps?
Max friction force = M g u
The equals M a when it is on the verge of slipping.
Therefore a = u g is the maximum deceleration rate. u is the static coefficient of friction, 0.27
a = 2.646 m/s^2
To get the stopping distance X, use
V = sqrt (2 a X)= sqrt (2 u g X)
Convert the V = 59.7 km/hr to m/s units before using that equation.