Mountain climber - center of gravity, tension, angles

AI Thread Summary
The discussion revolves around a physics problem involving a mountain climber rappelling down a vertical wall. The climber's weight is 770 N, and the rope is attached 15 cm to the right of the center of gravity. Participants are tasked with calculating the tension in the rope and the contact force exerted by the wall on the climber's feet. Various proposed answers for the tension and contact force direction are provided, with some participants expressing uncertainty about how to approach the problem. The solution emphasizes applying equilibrium conditions, where the sum of forces and torques must equal zero.
BlueSkyy
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Homework Statement



A mountain climber is rappelling down a vertical wall (the figure below ). The rope attaches to a buckle strapped to the climber's waist 15 cm to the right of his center of gravity. If the climber weighs 770 N, find (a) the tension in the rope and (b) the magnitude and direction of the contact force exerted by the wall on the climber's feet.

https://chip.physics.purdue.edu/protected/GiambattistaMimg/chapter-08/fig-064.gif

# (a) 750 N; (b) 310 N at 22° above the horizontal
# (a) 730 N; (b) 330 N at 19° above the horizontal
# (a) 730 N; (b) 300 N at 16° above the horizontal
# (a) 750 N; (b) 330 N at 19° above the horizontal
# (a) 770 N; (b) 300 N at 16° above the horizontal

Homework Equations



basic equations...
F = ma
sin = o/h
cos = a/h
tan = o/a

The Attempt at a Solution



well...
i don't really know where to start.
i have examples of the rope being attached to the climber's CoG, so i tried to work the problem like one of those and came out with a tension of 744 N.

any help would be GREATLY appreciated!
 
Physics news on Phys.org
This is an equilibrium problem, so apply the conditions for equilibrium: The forces (in any direction) must add to zero and the torques (about any point) must add to zero.
 
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