chris667":1h6rwn99 said:lewis1641":1h6rwn99 said:when you are hit by a car a lehmet helps by protecting your head against solid objects. like the car. and the ground.
No.
A helmet protects against linear impact by slowing down the rate at which your head makes contact with the ground. It only works at low speeds, like when you fall off your bike at 10mph.
At higher speeds, you are more likely to suffer what's known as a rotational head injury. This is where your head twists as it hits an object at speed, such as the car windscreen heading towards you at 50mph.
Helmets don't help at all here; because they effectively make your head wider the speed at which it rotates when it twists is faster, so there are a lot of arguments to suggest a helmet reduces your chances of survival at these speeds. There are some experimental helmets designed for motorcycling that have a second skin which slides off on impact, but because cyclists need well ventilated lids this is a technology that won't be coming over to bikes.
I'm sorry to say that if you are involved in an accident involving a car, the chances are you're stuffed, helmet or no.
fair enoughski. i didnt realise that. just goes to show the marketing of stuff - i feel invincible with my lid on!