I would like to know if it is possible for cars to achieve a deceleration value of more than 1 g, and if its possible, how, just a general idea would be helpful?
Thank you in advance.
Yes it is possible to exceed the braking deceleration of 1g. While the general rule is that the maximum brake force will be limited by the weight of the vehicle, in fact it is a factor of the adhesion coefficient of the road. So your max deceleration rate will be 1g×mu where mu is the road friction coefficient. If mu is higher than 1 than the max deceleration will be more than 1g.
But isnt the maximum coeff of friction 1, because the curves for mu versus slip for various road conditions, what I observed is the max value of mu was 1.
When I attended Engineering School in the seventies, we debated the idea that one of the possible benefits of Electric Vehicles was to power each wheel with its own motor, and control torque at each one to keep steering and braking ability on ice, including rotating the wheel in the opposite direction. May be you could explore that concept on higher adhesion surfaces. Tires vs Mu would be part of the equation.
Alexander added an important point -- racing cars generate downforce which drastically increases normal force. F1 has seen radical changes in aerodynamics and regulations over the years, but the cars have typically generated 2-3x their weight in downforce. I can't find a source now, but I recall that drag from the aerodynamics components alone (wings, diffusers) slowed F1 cars at over 1g without touching the brakes.
Mr. Stephen I think your are mixing concepts. The main purpose of the down-force is to help the car stick more on the road when a high speeds are achieved so to create a negative force that pushes the car to the road, that's because all of the rear diffusers, wings, spoilers and so on.
There are some high performance cars that may have movable spoilers on the back of the car to reduce the car breaking distance at high speeds.
Agree with Michael. Some people are confusing different physical phenomena here.
Say you are driving your car at a speed of 144 km/h i.e.40 m/s the if your press the brake and managed to stop the car in a disatance of 4 meters that means your car decelerated at 10 m/s^2 which is >g. So it is possible my dear and it all depends on tyres type,aerodaynamic forces ,friction coefficient and car design.
Stopping from 40 m/s with a deceleration of 10 m/s² will stop you in 4s not 4 m.
The formula for distance is V_avg x t (t = time) or 1/2 a x t². Anyway the result is 40 m.
Small correction for Alexander's point. I wish the friction coefficient between an F1 tyre and the road surface was 5! Actually it's never any where near that number. But it is well over 1. And F1 cars can sometimes decelerate at close to 5'g', which is a simple function of that high tyre grip combined with the aerodynamic downforce, and the component due to aero drag.
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