Super Cars & Their Top Speeds

[Akash1886]

Friends,

In one of the magazines, came across this brilliant article and thought to share the same with you all.



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Credit: Shine GNN Magazine, October Edition.

Regards

Akash

 

[SilverEyez]

Re: Super Cars and Their Top Speeds

Wow!!
Would love to read in detail about this article, a digital print of this article should be published in forums too.

 

[Thangavel]

Re: Super Cars and Their Top Speeds

Friends,

In one of the magazines, came across this brilliant article and thought to share the same with you all.

View attachment 249470

View attachment 249471​

Credit: Shine GNN Magazine, October Edition.

Regards

Akash

Cool
Since you mentioned source as Shine GNN, I searched and came across this website www.shinegnn.com which says the magazine is free. However I couldn't find any section related to car .May be this is different website and not related.
While searching for cars mentioned in the post, I came across this interesting article:
https://www.popularmechanics.com/cars/car-technology/g3125/bugatti-chiron-test-drive/

In the article I saw this comment by Wallace regarding Bugatti Chiron:

Even at 261 mph the wheel and tire has to withstand extreme forces. The valve cap on each wheel weighs 2.5 grams, but it equates to 16 pounds at 261 mph. As the speed moves even higher, the loads increase exponentially.

How is this possible? How can 2.5gm valve weigh 16 pounds, ie about 7.6 kg just because of speed ? Can someone explain this?
Thanks in advance

 

[Akash1886]

Re: Super Cars and Their Top Speeds

In the article I saw this comment by Wallace regarding Bugatti Chiron:


How is this possible? How can 2.5gm valve weigh 16 pounds, ie about 7.6 kg just because of speed ? Can someone explain this?

Well, @carcommentor will be best one to tell this. My Mathematics has always made me a butt of jokes

Regards

Akash

 

[bhvm]

Re: Super Cars and Their Top Speeds

Cool

How is this possible? How can 2.5gm valve weigh 16 pounds, ie about 7.6 kg just because of speed ? Can someone explain this?
Thanks in advance

Well, Its not like the valve cap is eating burgers and becoming bulked up.
But as things spin, centrifugal and centripetal forces start acting up, increasing the 'virtual' weight for the spinning object. Yeah there is serious science to be learnt with those CD exploding videos on youtube.

Waiting for @carcommentator for some proper scientific explanation.

 

[carcommentor]

Re: Super Cars and Their Top Speeds

Cool ..........

In the article I saw this comment by Wallace regarding Bugatti Chiron:
How is this possible? How can 2.5gm valve weigh 16 pounds, ie about 7.6 kg just because of speed ? Can someone explain this?
Thanks in advance

As @bhvm has pointed out, it is due to centripetal force on the valve.

The Centripetal Acceleration = (radians per sec)^2 x radius.

Let's do the calculation. The Bugatti Chiron has a Michelin Pilot Sport Cup Tires size of 285/30R20 front tyres so inner diameter is 20 inch (0.508 metes) and outer diameter is about 26.8 Inch (0.68072 meters).


Distance traveled by this tire in 1 rev = 2 x pi x r = 2 x pi x (0.68072/2) = 2.13854 meters.
The speed of Bugatti Chiron is 261 mph which in meters per minute = 261x26.822 = 7000.65 meters per Minute.

At that speed, the tire revolution per minute = 7000.65 / 2.13854 = 3273.57 rpm.

We need to convert this to radians per second. As you all know, there are 2 Pi radians per revolution and 60 seconds per minute so 3273.57 rpm = (3273.57 x 2 pi ) / 60 = 342.80 radians per sec.
The valve is located on the rim, so we will take the inside radius of the tyre , which is 0.508 / 2 = 0.254 meters. Thus the Centripetal Acceleration on the valve = (radians per sec)^2 x radius = (342.807)^2 x 0.254 = 29849.2 m/sec^2
We all know that the acceleration due to gravity is 9.8 m/sec so, the
valve will experience 29849.2 / 9.8 = 3045.84 Gs hence the 2.5 gm valve will weigh (apparent weight due to G force) 2.5 x 3045.84 = 7614.6 gms = 7.61 kg = 16.78 pounds !

HTH

 

[Thangavel]

Re: Super Cars and Their Top Speeds

As @bhvm has pointed out, it is due to centripetal force on the valve.

​

Let's do the calculation. The Bugatti Chiron has a Michelin Pilot Sport Cup Tires size of 285/30R20 front tyres so inner diameter is 20 inch (0.508 metes) and outer diameter is about 26.8 Inch (0.68072 meters).


Distance traveled by this tire in 1 rev = 2 x pi x r = 2 x pi x (0.68072/2) = 2.13854 meters.
The speed of Bugatti Chiron is 261 mph which in meters per minute = 261x26.822 = 7000.65 meters per Minute.

At that speed, the tire revolution per minute = 7000.65 / 2.13854 = 3273.57 rpm.

We need to convert this to radians per second. As you all know, there are 2 Pi radians per revolution and 60 seconds per minute so 3273.57 rpm = (3273.57 x 2 pi ) / 60 = 342.80 radians per sec.
The valve is located on the rim, so we will take the inside radius of the tyre , which is 0.508 / 2 = 0.254 meters. Thus the Centripetal Acceleration on the valve = (radians per sec)^2 x radius = (342.807)^2 x 0.254 = 29849.2 m/sec^2
We all know that the acceleration due to gravity is 9.8 m/sec so, the
valve will experience 29849.2 / 9.8 = 3045.84 Gs hence the 2.5 gm valve will weigh (apparent weight due to G force) 2.5 x 3045.84 = 7614.6 gms = 7.61 kg = 16.78 pounds !

HTH

I thought at the most I will get theoretical explanation , not complete step by step worked out calculation Thank you !