Why do we take small steps while walking on ice?

Question

> When we walk on ice we should take small steps. Small steps ensure: > > a.)larger friction. > > b.)small friction. > > c.)larger normal force. > > d.)smaller normal force. The correct answer is smaller friction. But I think that small steps give larger normal force and more the normal, more the friction. When we take small steps while walking on ice, do we ensure smaller or larger friction and how?

Answer 1

Good reasoning in your objection. But it ignores the fact that the Normal Force is independent of any Forces in the horizontal direction. Since the Force you apply to the ice to move forward is horizontal it has no effect on the Normal force. This Force your foot applies to the ice causes a reaction Force by the ice on your foot of equal magnitude in the opposite direction. This is Newton's 3rd Law; Action/Force => Equal and opposite Reaction/Force. ......... Now you take small steps because the frictional force which allows the reaction Force to exist is F(friction) = u F(Normal) = u m g. If your foot applies a Force greater than this, you will slide, not push off. So you are limited in the Force you are permitted to apply by your weight, mg, and the coefficient of friction, u.