Static Equilibrium. Man on Ladder

AI Thread Summary
The discussion focuses on solving a static equilibrium problem involving a ladder leaning against a wall. The ladder's weight and the weight of a person standing on it are given, along with their respective distances from the base. Participants discuss the need to establish a point of rotation at the base of the ladder to simplify torque calculations. They emphasize setting up equations for forces in both the x and y directions, as well as for torque, to find the force exerted by the wall and the normal force from the floor. The conversation highlights the importance of understanding torque direction in the calculations.
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Homework Statement


A 9.8 m ladder whose weight is 257 N is
placed against a smooth vertical wall. A
person whose weight is 464 N stands on the
ladder a distance 1.9 m up the ladder. The
foot of the ladder rests on the floor 7.056 m
from the wall.
Calculate the force exerted by the wall.
Answer in units of N.
Calculate the normal force exerted by the
floor on the ladder.
Answer in units of N.


Homework Equations


Tnet = 0
Fnet = 0


The Attempt at a Solution


I know I need to pick a point of rotation. I figured I would pick the bottom of the ladder where it makes contact with the floor. That will eliminated the torque due to the friction force and the normal force between the ladder and the floor. The other forces are the weight of the ladder, weight of the man, and the friction force of the ladder and wall. I'm kind of lost now.
 
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Have you set up a system of equations? You should have an equation for forces in the x-direction, one for forces in the y-direction, and one for torque.
 
X: Fwmanx + Fwladderx = Fwall
Y: Fwmany + Fwladderx = Fn
Torque: I'm confused on how to determine clockwise or Counterclockwise Torque.
 
I figured it out thanks
 
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Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
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