- #1

Karol

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## Homework Statement

A man of mass 70[kg] pules a box at an angle 10

^{0}. the static coefficient of friction between his legs and the floor is 0.6 and the kinetic coefficient between the box and the floor is 0.3

What's the maximum's box's mass

## Homework Equations

Friction: f=μN

## The Attempt at a Solution

The horizontal force the man can apply:

$$70\cdot 9.81\cdot 0.6=412.02=F\cdot \cos 10^0\rightarrow F=418.38$$

The vertical component of F raises the box: ##F\cdot \sin 10^0=418.02\cdot\sin 10^0=72.65##

the force needed to pull the box:

$$(mg-F\cdot \sin 10^0)0.3=412.02\rightarrow (mg-72.65)0.3=412.02\rightarrow m=147.4[kg]$$

It should be 164.85