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\displaystyle l = 1,0\, \textrm{m};\quad mg = 39,3\, \textrm{N}; \displaystyle \cos{\alpha} = 3/5;\quad \sin{\alpha} = 4/5

Momentjämvikt kring kontaktpunkten mellan stången och golvet ger:

\displaystyle N_A \cdot 5l - mg \cdot 3l\cos{\alpha} = 0 \displaystyle N_A = \frac{3}{5}mg\cos{\alpha} = \frac{9}{25}mg = 14,1\, \textrm{N}

Kraftjämvikt horisontellt ger:

\displaystyle f = N_A\sin{\alpha} = \frac{9}{25} mg\sin{\alpha} = 14,1 \cdot \frac{4}{5} = 11,3\, \textrm{N}

Kraftjämvikt i vertikal led ger:

\displaystyle N - mg + N_A\cos{\alpha} = 0 \displaystyle N = mg-N_A\cos{\alpha} = mg -\frac{9}{25}mg \cdot \frac{3}{5} = \frac{98}{125}mg = 30,8\, \textrm{N} \displaystyle {\mu} = \frac{f}{N} = \frac{11,3\, \textrm{N}}{30,8\, \textrm{N}} = 0,37