Kinetic friction on an incline problem

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Homework Help Overview

The problem involves a mountain climber lowering himself down a cliff while tied to a rock, with a frictionless pulley involved. The scenario includes specific measurements of distance, time, and masses, and requires determining the climber's acceleration and the coefficient of kinetic friction between the rock and the mountain.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the implications of constant acceleration and kinematics in solving for the climber's acceleration. Some express confusion regarding the setup, questioning the incline of the cliff and the positioning of the pulley and rock.

Discussion Status

The discussion is ongoing, with some participants attempting to clarify the problem's parameters while others are exploring the application of kinematic equations. A diagram has been provided to aid understanding, but questions about the setup remain unresolved.

Contextual Notes

There are uncertainties regarding the incline of the cliff and the exact positioning of the pulley and rock, which may affect the interpretation of the problem. The original poster has requested assistance, indicating a need for further clarification on these points.

-Justin-
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Hey guys this question has been stumping me to death! Any help at all would be greatly appreciated.

A mountain climber has tied himself to a rock and has begun to lower himself down a cliff. The rope passes over a frictionless pulley. At time t=0, the rock and the mountain climber are not moving, the mountain climber drops 10 meters in 6.2 seconds. The mass of the climber is 70kg, and the mass of the rock is 500kg. The mountain climber is directly vertical and the rock is sitting at 15 degrees above the x-axis.
What is the mountain climber's acceleration while he drops? Assume it is a constant acceleration.
Find the coefficient of kinetic friction between the rock and the side of the mountain.
 
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I don't really understand the problem. Is the cliff also inclined at 15 degrees above the x-axis (doubtful!)? Where is the pulley? Where is the rock? A diagram would be helpful.
 
here is a picture of the drawing.

click either one of the links
http://img.photobucket.com/albums/v201/b16eh2/cc93d412.jpg
 

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For the first question, since you're told to assume constant acceleration, the question becomes a simple kinematics question. At t = 0, u = 0. At t = 6.2s, s = 10m. Apply your kinematics equation.

With the first part, you can get the acceleration of the mountain climber. Then, you should next find out the force the rock exerts on the climber, and from there you can find out the coefficient of friction.
 

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