We are able to walk bcaus of newtons 3 law. So why should we not be able to walk on frictionless surface?

Question

force can be applied even without contact

you can exert muscular force on slipery surface. You can do it just by pushing it with force.

to answer dr_saini 9th grade text book says we walk because of newtons 3rd law, and few other text state that it is because of friction.

Answer 1

a frictionless surface doesnt provide the reaction force against the force u provide. your force on the surface is actually applied opposite to the way you walk. the horizontal resolved part needs to be supported by a reaction force which is indeed nothing but friction. in other words, it is friction that works in the direction of your walking. so if no friction-no way you can walk.

Answer 2

Like so many things in physics, this seems puzzling because it concerns itself with extremes and perfections. No, there is nothing theoretically wrong with walking on a frictionless surface. You would do what you always do: press down with one foot to lift the other, and move that one forward, plant it, push down to pick up the first, and so on. The problem is that it is as a practical matter impossible to push exactly directly down. You are always pushing a little to the side. This tiny bit of force is enough to send you sliding on a frictionless surface. Normally, that force is cancelled by the high static coefficient of friction between your shoes and the ground/floor.

Wheeleed transportaion, however, relies explicitly on static friction. As the wheel rolls forward, it is constantly pushing backwards, which causes the ground to push forward. On a frictionless surface, the wheels start to skid immediately after you start rolling, so while you can move on wheels on a frictionless surface, it's a really bad idea if you intend to control it.

Answer 3

you can exert muscular force on slipery surface. You can do it just by pushing it with force.

But your pushing on a "frictionless surface" so therefore there is nothing to "push ON' or another way of putting it: say you have a Frictionless Toilet, whenever you used it, by the time you stood up, the toilet would be SPOTLESS. No water, no waste, NOTHING there on the toilet. Completely waterless. Why? Because there IS NOTHING FOR ANYTHING TO GRAB HOLD OF AS FAR AS FRICTION, THERE IS NOTHING TO TOUCH, you're hand would simply "slip off."

Answer 4

Not being able to walk on frictionless surface has nothing to do with 3rd law, your action will indeed generate equal and opposite reaction regardless of friction.

Except that the vector of your force will not be in favour of walking movement when there is no friction

Answer 5

Sorry, the question is flawed. It assumes we can not walk on a frictionless surface, when in fact we can. We just can't walk on it in the usual way by pushing backwards against the surface. When on a frictionless surface, the force has to be exerted downward while extending mass forward to produce forward motion.

To see this in action, find a film of the various ways they walked on the moon. The best way was a sort of one leg hopping motion that did not depend on the surface friction. It took advantage of the Moon's low gravity instead.

;-D Thanks Apollo.

Answer 6

You are looking at the 3rd law of motion in a limited sense.
You are just looking for a motion as a reaction of an action, but that isn't the case at all.

While we are walking on a fricionless surface the action in this case is "walking" and there are many corrosponding actions in this case,
eg.
If you fall down its a kind of reaction
If the surface gets scartched etc it is also a reaction etc etc

Answer 7

its the friction force applied by the surface that's come into play in the action reaction pair (i.e. the newtons third law) so we find it difficult to walk on friction less surface

Answer 8

because of newtons first law, 'Objects in motion tend to stay in motion, and objects at rest tend to stay at rest unless an external force acts upon them.'

The external force needed to walk is friction. A slippery surface by definition has little or no friction.

Answer 9

we can jump on frictionless surface because of 3rd law. walking cannot be done on frictionless surface since 3rd law is applicable only if there is resistance. if there is no resistance (here friction) 3rd law is not applicable.

without contact you can transfer force but only electro-magnetically.

Answer 10

Remember the "equal and opposite" part of Newton's laws? In walking we push ourselves forward by pushing back on the ground... without traction there is nothing to push against.

Aloha