in case of f1 cars the road surface is even and it does not consists of stones and pebbles and also f1 has to maintain a high grip with road surface but in case of ordinary tyres they r to be driven in rough areas n also surfaces which r uneven so to adjust itself and balance vehicle at variable speeds in such uneven surface .
hence many times v see small atones suck into the grooves
so they can have more traction
You should change tires when you look at the grooves and they are ground pretty smooth. You want grooves in your tire so that it has good traction. If you put a nickel in-between your grooves and it doesn't stick out, then your tires are still good.
Car tires cover the wheel rim. They are made of rubber with grooves to provide traction and act as a cushion to absorb the shock from large bumps or jolts.
Deeper grooves improve traction for off road use but are noisy when on road use.
To increase friction
When it rains, cars sometimes hydroplane because the water underneath the tires supports the weight of the car and causes it to loose traction. Grooves give another channel for water to escape. As for off-road cars, the tire grooves are not much deeper rather they are larger and have more room to go up and down. In my Jeep Wrangler, the tire grooves are the same depth as an Acura TL and a Honda minivan. Maybe on other off-road cars they help the car travel through gravel, rock, sand, and snow to gain more traction.
Why would you? They're your tires, you bought them.
Because they have to get a grip in mud, grass and soft ground in general.
So the water you drive through will be channelled through the grooves to prevent aquaplaning.
Tires need the grooves to be able to get a grip when weather is not the best. They provide a place for water, ice and snow to go and allow the rubber tread to make contact with the road. Racing cars often use tires with no grooves at all, but the weather has to be dry and the pavement clean. On a passenger car, even a little water can cause hydroplaning, where the tire is on water rather than the pavement.
BF Goodrich have the traction T/A ,Racing tires are specially fornulated rubber, some have grooves cut into them for added friction,their are also chemicals that could be sprayed on for temporary traction.
Tire grooves channel and disperse the water on wet roads. If it weren't for grooves, your tires would be 'aquaplaning' on every patch of water, and not gripping the surface.