A ladder of length 2L and mass M is positioned on level ground leaning against a wall such that the angle between the ladder and the horizontal is α. The coefficient of static friction between the ladder and the wall and between the ladder and the ground is μstatic = 0.66. The centre of mass of the ladder is halfway along it. A. For the ladder to be in mechanical equilibrium: i. Write down equations for the total x- and y-components of the 5 forces acting on the ladder. ii. Consider torques about the centre of the ladder. In which direction (into or out of the page) does the torque due to each of the 5 forces force act? iii. Write down an equation for the sum of the torques about the centre of mass of the ladder.

A ladder of length 2L and mass M is positioned on level ground leaning against a wall such that the angle between the ladder and the horizontal is α. The coefficient of static friction between the ladder and the wall and between the ladder and the ground is μstatic = 0.66. The centre of mass of the ladder is halfway along it. A. For the ladder to be in mechanical equilibrium: i. Write down equations for the total x- and y-components of the 5 forces acting on the ladder. ii. Consider torques about the centre of the ladder. In which direction (into or out of the page) does the torque due to each of the 5 forces force act? iii. Write down an equation for the sum of the torques about the centre of mass of the ladder.

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.92RP: The test specimen AB is placed in the grip of a tension-testing machine and secured with a wedge....

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