- #1

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## Homework Statement

The rectangle in the drawing is held by the horizontal rope and the friction on the wall.

What's the minimal coefficient of friction

## Homework Equations

Friction force: f=μN

## The Attempt at a Solution

Moments round the point of contact with the wall. the side of the rectangle is a, half the diagonal to the center is ##\sqrt {a}##. the distance of the CoM to the wall: ##\sqrt {a}\cdot\sin 55^0=1.16a##

$$1.16a\cdot mg=T\cdot \sin 10^0\rightarrow T=6.68mg$$

$$6.68mg\cdot\mu=mg\rightarrow\mu=0.15$$

It should be 0.3