How hard would you have to stop a car, and at what speeds, to cause any brain damage?

Question

Are most cars even capable of breaking hard enough to generate any G forces to cause a concussion?

For instance, if a person driving at 30 mph in an ordinary car slammed his breaks, would he incur a concussion?

What about when the car doesn't come to a complete stop? For instance, if a person driving 60 mph down the highway hit his breaks and, over about ten or fifteen feet, slowed to around 30 mph, would sufficient forces be exerted to deliver any damage?

Answer 1

This could happen at any speed, it depends on the car and the person....

Answer 2

The G forces in a passenger car don't exceed much more than 1G in braking.  Some race cars can go up to around 4G.

But when you hit your head against something, you get much higher G forces.  Race car drivers have survived 100G crashes, although they got some good injuries in the process.

Without an accident, it's unlikely to get a concussion in a car unless your head hits the window while you're four-wheeling or something like that.

Answer 3

If a car is traveling faster than 12 knots you will likely cause approximately 15.6 nanoliters of damage.