At what speed will a car flip over when it slides side-ways into a curb?
(Thanks to Reynier Cruz-Torres of MIT for suggesting the question.)
Answer: A speeding car failed to round a curve, slid sideways into a curb, and rolled over near my friend’s apartment. What is the minimum speed for this to happen? First we need to look at what happens in the collision. When the car hits the curb (a low barrier) at a high enough speed, it starts to rotate around the top of the curb. Gravity exerts a torque that counters this rotation. The angular momentum of the car will depend on its initial speed, the height of the curb, and the height of the center-of-mass (CM) of the car. The torque will depend on the width of the car. The mass of the car is irrelevant.
Let’s work out the physics and then estimate...
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