College Physics
1st Edition
ISBN: 9781938168000
Author: Paul Peter Urone, Roger Hinrichs
Publisher: OpenStax College
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Textbook Question
Chapter 9, Problem 8PE
(a) Calculate the magnitude and direction of the force on each foot of the horse in Figure 9.31 (two are on the ground), assuming the center of mass of the horse is midway between the feet. The total mass of the horse and rider is 500kg. (b) What is the minimum coefficient of friction between the hooves and ground? Note that the force exerted by the wall is horizontal.
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In the figure a 57 kg rock climber is in a lie-back climb along a fissure, with hands pulling on one side of the fissure and feet pressed against the opposite side. The fissure has width w = 0.15 m, and the center of mass of the climber is a horizontal distance d = 0.30 m from the fissure. The coefficient of static friction between hands and rock is μ1 = 0.35, and between boots and rock it is μ2 = 1.30. The climber adjusts the vertical distance h between hands and feet until the (identical) pull by the hands and push by the feet is the least that keeps him from slipping down the fissure. (He is on the verge of sliding.)
(a) What is the least horizontal pull by the hands and push by the feet that will keep the climber stable? (b) What is the value of h?
In the figure a 54 kg rock climber is in a lie-back climb along a fissure, with hands pulling on one side of the fissure and feet
pressed against the opposite side. The fissure has width w = 0.30 m, and the center of mass of the climber is a horizontal
distance d = 0.45 m from the fissure. The coefficient of static friction between hands and rock is μ₁ = 0.30, and between boots
and rock it is μ2 = 1.15. The climber adjusts the vertical distance h between hands and feet until the (identical) pull by the
hands and push by the feet is the least that keeps him from slipping down the fissure. (He is on the verge of sliding.)
(a) What is the least horizontal pull by the hands and push by the feet that will keep the climber stable? (b) What is the value
of h?
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In the figure a 60 kg rock climber is in a lie-back climb along a fissure, with hands pulling on one side of the fissure and feet pressed
against the opposite side. The fissure has width w = 0.30 m, and the center of mass of the climber is a horizontal distance d = 0.20 m
from the fissure. The coefficient of static friction between hands and rock is μ₁ = 0.30, and between boots and rock it is μ2 = 1.10. The
climber adjusts the vertical distance h between hands and feet until the (identical) pull by the hands and push by the feet is the least
that keeps him from slipping down the fissure. (He is on the verge of sliding.)
(a) What is the least horizontal pull by the hands and push by the feet that will keep the climber stable? (b) What is the value of h?
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Chapter 9 Solutions
College Physics
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