# Does the weight on a car's wheels decrease with increasing speeds? [duplicate]

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Ignoring the reduction in fuel weight as it burns, does the weight on a car's wheels decrease with increasing speeds? If so, by how much and is there a fomula for calculating that? At what speeds does it then become zero?

## marked as duplicate by Aaron Stevens, user191954, Chris♦, GiorgioP, John Rennie newtonian-mechanics StackExchange.ready(function() { if (StackExchange.options.isMobile) return; $('.dupe-hammer-message-hover:not(.hover-bound)').each(function() { var$hover = $(this).addClass('hover-bound'),$msg = $hover.siblings('.dupe-hammer-message');$hover.hover( function() { $hover.showInfoMessage('', { messageElement:$msg.clone().show(), transient: false, position: { my: 'bottom left', at: 'top center', offsetTop: -7 }, dismissable: false, relativeToBody: true }); }, function() { StackExchange.helpers.removeMessages(); } ); }); }); Mar 1 at 16:49

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• In the relativistic sense, no the mass of the car doesn't change. There may be some amount of lift generated by airflow, but that probably should/would be offset by the airflow pushing down in the car. – Kyle Kanos Mar 1 at 12:16
• A little bit but only driving eastwards and having latitude dependence. We shall look for duplicates. – Alchimista Mar 1 at 12:20
• Possible duplicate of Why do cars gain lift while going at a high speed? – Chris Mar 1 at 12:22
• – Alchimista Mar 1 at 12:33
• physics.stackexchange.com/q/299723 basically answers your question. Just add the the car doesn't stay still but moves and you are done. Unless you consider lifting etc but wouldn't be appropriate. Other answers to questions about weight at poles and equator will do the job as well. – Alchimista Mar 1 at 12:38

## 1 Answer

The weight of the wheels never decrease. If you are observing a car bouncing off the ground at high speed, it's not the weight decreasing, it's the aerodynamic lift due to Bernoulli's principle of pressure difference due to flow speed. But for specificity, the tire might stretch out radially at high rpm due to centrifugal force, but that's extremely negligible in a practical sense.