# Frictional Forces Physics 1 Problem

**1. The problem statement, all variables and given/known data**

7.) A 1520-N crate is to be held in place on a ramp that rises at 30.0° above the horizontal (see figure). The massless rope attached to the crate makes a 22.0° angle above the surface of the ramp. The coefficients of friction between the crate and the surface of the ramp are µ_{k} = 0.450 and μ_{s} = 0.650. The pulley has no appreciable mass or friction. What is the MAXIMUM weight *w* that can be used to hold this crate stationary on the ramp?

Picture of problem:

**2. Relevant equations**

F_{s} = μ_{s}F_{n}

F = ma

**3. The attempt at a solution**

I attempted by first mapping out the forces for F_{x} and F_{y}. I then solved for the normal force in order to replace it in the static friction force equation so as to be able to solve for the tension in the rope which I then found to be 1380 N. I am unsure whether this is the answer. Logically it somewhat makes sense that the tension in the rope must be equal to the weight of the mass on the other end to be completely still. Looking for some analysis of my answer and some pointers in the correct direction

**1. The problem statement, all variables and given/known data**

**2. Relevant equations**

**3. The attempt at a solution**

http://ift.tt/1lHapwV

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