How Does a Ladder in Equilibrium Affect the Forces on a Window and Ground?

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The discussion focuses on a scenario involving a ladder in equilibrium, where a window cleaner climbs a ladder that rests against a window. The key points include the need to calculate the force exerted on the window by the ladder just before it breaks, using torque equations and equilibrium principles. The user attempts to set up the torque equation but encounters difficulties in obtaining the correct force magnitude. Additionally, the user seeks assistance in determining the force on the ladder from the ground, indicating they have not yet started this calculation. The thread highlights the complexities of applying physics concepts to real-world scenarios involving forces and equilibrium.
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A 80 kg window cleaner uses a 16 kg ladder that is 5.5 m long. He places one end on the ground 2.1 m from a wall, rests the upper end against a cracked window, and climbs the ladder. He is 2.9 m up along the ladder when the window breaks. Neglect friction between the ladder and window and assume that the base of the ladder did not slip.

(a) Find the magnitude of the force on the window from the ladder just before the window breaks.Okay, so I know that since it is in equilibrium the sum of the torques must be 0. Therefore I can say \tau = 0 also \tau = \r F sin \theta

so \tau = \r F sin \theta ladder + \r F sin \theta man - \r F sin \theta window = 0

my book told me to set up the equation at the bottom of the ladder so I don't need to include the pavement, anyway when solving this, I get \tau = (1.1)(80)(9.8)sin(67.6) + (1.55)(16)(9.8)sin(67.6) - window = 0

with that I get 1021.29 which is wrong, any ideas?

Also there is an r in all those equations, but I don't get the formatting, so I can't put it in, but I got the radius of the guy and the ladder in there. also I once solved for 2.9 as the distance he was up the ladder in the y direction, also didn't work

(b) Find the magnitude and direction of the force on the ladder from the ground just before the window breaks.Dind't start this yet, as I am not done part A
 
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Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .

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