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sach963
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When a person is running is frictional force forward or backward?
I do not have good knowledge of
I do not have good knowledge of
Both, but for steady speed the net momentum transfer from the ground is forward to counter air resistance (unless on treadmill).sach963 said:When a person is running is frictional force forward or backward?
The horizontal force (friction) on the shoe is backward in early stance phase, and forward in late stance phase, See the smaller component in the plot in the video above: negative = backwards, positve = forward. The bigger, always positive, component is the vertical force on the shoe (normal force).sach963 said:So, this means that friction between ground and shoe is forward?
Sorry, the wrong words got cut and pasted in my response, here is the correct one:Chandra Prayaga said:Much of the confusion in all similar situations arises because of using imprecise language. For example, regarding the question by sach963, "So this means friction force between ground and shoe is forward?", there are TWO forces of friction between ground and shoe. One is the force by shoe on ground, and the other by ground on shoe. It is the force between ground and shoe that needs to be ultimately forward so that the person is propelled forward by it.This is clearly stated by A.T. above, "force on the shoe". When your shoe pushes back on the ground, the ground pushes forward on your shoe.
With air resistance or during acceleration the average force will be forward. On the treadmill the average horizontal force is approximately zero.Chandra Prayaga said:t is the force BY ground ON shoe that needs to be ultimately forward so that the person is propelled forward by it.
It's not mine. It comes from here:Chandra Prayaga said:Incidentally, A.T., that was a very nice video. Can I show it in my class?
The direction of frictional force when running is opposite to the direction of motion. This means that when you are running forward, the frictional force will act in the backward direction.
Frictional force is important when running because it helps to provide grip and traction between your feet and the ground. This allows you to push off the ground and move forward without slipping.
The weight of a runner has no effect on the direction of frictional force. The direction of frictional force is determined by the direction of motion, not the weight of the object.
Yes, the direction of frictional force can change while running. For example, if you suddenly change direction or stop, the direction of frictional force will also change accordingly.
The type of surface can affect the direction of frictional force when running. For example, if you are running on a wet or slippery surface, the direction of frictional force may not be as strong and can cause you to slip or lose traction.