00:01
Here we have a flat or unbanked curve on a highway has a radius of 170 meters.
00:08
A car goes around the curve at 25 meters per second, and we want to figure out what friction force needs to be acting to keep the car from sliding.
00:20
So in the radial direction here, we have the friction force acting, and then we have the mass times of centrifugal acceleration.
00:28
So if you know the velocity, we can say that that's v squared over r.
00:34
Now, if we did a free bi diagram in the, looking at this way, we'd have the weight, the normal force, and the friction force.
00:42
So that just tells us that the normal force is the weight, and the maximum friction force is mu -s times the weight, or the normal force.
00:56
So that means the maximum friction force is mu -s times the minus...