If I let air out of my tires to increase surface area on sand; wont that just reduce the pressure on the sand too? Is traction NOT a function of both pressure and surface area? Physics

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If I let air out of my tires to increase surface area on sand; wont that just reduce the pressure on the sand too? Is traction NOT a function of both pressure and surface area? Physics

In: Physics

5 Answers

Anonymous 0 Comments

If you have a block that has a square base of 2 cm by 2 cm that is 10 inches tall you can either have it stand up on the 2 by 2 base or the 10 by 2 side. The side has much more surface area but less mass on top of each individual point, while the 2 by 2 has less surface area but much more pressure. Changing the surface area on an object (but leaving the mass the same) generally doesn’t affect friction, although I’m not sure how sand would affect this. This probably doesn’t answer your whole question but hopefully it’s good enough!

Anonymous 0 Comments

Gravity is the force being applied here. Reducing air pressure in the tire just means that gravity will flatten the tire (decreasing the volume inside) until the pressure force rises enough to counteract gravity. This results in the same force on the ground, but a flatter contact surface.

Anonymous 0 Comments

From a high school physics standpoint, traction just comes from force. The area over which the force is applied is irrelevant. *However*, on sand, the sand wants to slide out from under the tires. By resting on more sand, it becomes more difficult for all of the sand to slide, and so traction is significantly improved.

Anonymous 0 Comments

Reducing the air pressure in your tires makes the tire softer. A softer tire can conform to the terrain better than a hard one

Anonymous 0 Comments

The pressure in your tires is irrelevant apart from the surface area change. Just because there is less pressure in your tires doesn’t mean your car weighs any less or imparts any less force on the sand.