A person is standing on a hill that is sloped at an angle of a with respect to the horizontal. The person's legs are separated by a distance d, with one foot uphill and one downhill. The center of mass of the person is at a distance h above the ground, perpendicular to the hillside, midway between the person's feet. Assume that the coefficient of static friction between the person's feet and the hill is sufficiently large that the person will not slip. N₁ d (Part a) What is the magnitude of the normal force on each foot (N₁ > N₂)? Express you answer in terms of some or all of the following: m (the mass of the person), alpha for a, h, d and g. Use sin(), cos() and tan() as appropriate. N₂ α (Part b) How far must the feet be apart so that the normal force on the upper foot is just zero? This is the moment when the person starts to rotate and fall over. Express you answer in terms of some or all of the following: m, alpha for a, h and g. Use sin(), cos() and tan() as appropriate.

A person is standing on a hill that is sloped at an angle of a with respect to the horizontal. The person's legs are separated by a distance d, with one foot uphill and one downhill. The center of mass of the person is at a distance h above the ground, perpendicular to the hillside, midway between the person's feet. Assume that the coefficient of static friction between the person's feet and the hill is sufficiently large that the person will not slip. N₁ d (Part a) What is the magnitude of the normal force on each foot (N₁ > N₂)? Express you answer in terms of some or all of the following: m (the mass of the person), alpha for a, h, d and g. Use sin(), cos() and tan() as appropriate. N₂ α (Part b) How far must the feet be apart so that the normal force on the upper foot is just zero? This is the moment when the person starts to rotate and fall over. Express you answer in terms of some or all of the following: m, alpha for a, h and g. Use sin(), cos() and tan() as appropriate.

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter14: Static Equilibrium, Elasticity, And Fracture

Section: Chapter Questions

Problem 64PQ: A One end of a metal rod of weight Fg and length L presses against a corner between a wall and the...

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