Air Pressure in a Car Tyre Increases During Driving, Here’s Why

BY Team Aakash Byju's

Palm Tree
Palm Tree

Consider the movement of particles inside a substance. We know that the particles are not at rest and will move or rotate from one place to another within their chemical structure.

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Palm Tree

We can increase the speed of this motion of particles by providing energy in the form of heat. This means that heat increases the pressure on the molecules/particles.

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Palm Tree

Now consider a moving car and observe its tyres. There will be friction between the tyre and the road.

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Palm Tree

During driving, the work is done against this frictional force which is converted into heat.

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Palm Tree

Or we can say that the external energy is applied to the tyre due to which it moves in a certain direction.

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Palm Tree

Now, this energy causes an increase in the temperature of gas molecules inside the tyre.

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Palm Tree

Though the temperature is raised for the molecules of the tyre, the volume of the tyre remains constant. i.e., the size of the tyre neither increases or decreases.

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Palm Tree

The number of molecules is also constant as we are not adding any molecules, nor are we taking them out.

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Palm Tree

So, per Gay-Lussac’s law, at constant volume (of tyre) pressure on the tyre increases as the temperature increase by heat energy applied.

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Palm Tree

This is why the pressure in a car tyre increases when you drive.