Solving a Ladder Problem: Finding Max Tension in a Rope

AI Thread Summary
The discussion focuses on calculating the tension in a rope securing a ladder against a wall, considering the ladder's weight, the weight of a man climbing it, and the friction involved. Participants emphasize the importance of using moments and force equations to analyze the system, suggesting that selecting the foot of the ladder as the pivot point simplifies calculations. There is clarification that the maximum tension in the rope occurs just before the ladder slips, indicating a critical point in the analysis. The user shares their equations and acknowledges a mistake in their initial approach, ultimately finding a solution. The conversation highlights the complexities of static equilibrium in physics problems involving ladders and ropes.
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Homework Statement


A uniform ladder of weight WL and length L has its top against a vertical wall with friction coefficient
μW and its foot on a smooth horizontal floor. A rope is attached to the foot of the ladder and secured
to the base of the wall, with the ladder making an angle α with the horizontal. If a man of weight WM
climbs the ladder, determine the tension in the rope when the man has climbed a distance d up the
ladder. What is the maximum tension in the rope?


Homework Equations


F=ma, applied to the contact with the wall, the floor and rope.


The Attempt at a Solution


So i know i have to use the moments of a force about a point, and that point doesn't matter, but itd be really helpful to show me which one is the easiest from a solving purpose. I need help with the maximum tension in the rope part, can't think of anything to be honest.
 
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Pick your favorite point! Just do it. (Hint: Pick one end of the ladder. Even better, pick both.)

In addition to moments, use force equations.
 
Ok, I am getting that T = R (normal with vertical wall) as there are no other forces in that direction. But that seems a bit simple no? Is the maximum tension in the string, the tension just before it breaks yes? So the tension when the the ladder is about to slip?

This is what happens when you leave 15 physics questions until the last night of your christmas break. Hahahahah.

Edit- My equations;
T = R
N - Wm- Wl+ Fr= 0

Torques at Foot of ladder;
-RLSina= WmDCosa +1/2. Wl LCosa
 
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Found my mistake, easy enough in the end.
 
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I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
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