As a person is walking up a stationary ladder, what happens to the magnitude of the forces Fn1 and Fn2?
Magnitude Fn1 Magnitude of Fn2
A: decreases decreases
B: decreases increases
C: increases decreases
D: increases increases
it might be hard to see the choices here for this multiple choice question so I made a table for it in the attachment to make the choices clearer.
b) Conceptual question: Without using numbers or any numerical calculations (only letters and symbols allowed) prove that what you got for part a is correct for this question (use principles of physics and show in formulas and equations as you would if numbers were provided and you were trying to calculate it).
ΣFx = ma, ΣFy = ma, and ΣT(torque) = 0
The Attempt at a Solution
a) For "part A" I would have to choose option "C" because if she walks up the ladder, doesn't Fn1 get larger because not only is she getting further and further away distance wise from Fn1 thus creating a larger torque. But she is also making the lever arm from Fn1 to her larger also, thus making the torque larger. And for the same two reasons wouldn't the magnitude at Fn2 begin to decrease as she approaches Fn2 and gets closer and closer?
b) For "part B" I know that they want me to explain and prove what I got for an answer in "part A" is correct using only letters and the principles of physics, but I do not know where exactly to start.
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