(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The person in This picture weights 170lbs. A seen from the front, each light crutch

makes and angle of 22degrees with the vertical. Half of the persons weight is

supported by the crutches. The other half is sipported by the vertical forces

of the ground on the person's feet. Assuming that the person is moving with

a constant velocity and the force exerted by the ground on the crutches acts

along the crutches, determine (a) smallest possible coefficient of friction

between crutches and ground and (b) the magnitude of the compression force

in each crutch

2. Relevant equations

F=ma

3. The attempt at a solution

I have first drew a free body diagram for one side and I get my

forces to be this.

x forces are -fk

y forces are -mg, n

I determined that each crutch has 42.5 lbs of force

I converted the 42.5 lbs to 189n

I solved the n force to be 202n by drawing a triangle and then using sin22(189)

= 70.8n. Then getting 202n using pyth. theraom.

Am I starting this correctly?

Thanks,

Kevin

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

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Friction and Magnitude Problem

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