The homogeneous beam of mass 5 kg indicated in the figure is in equilibrium and supported at points A and B. Calculate the reactions at the supports.
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Explanation:
Sum of moments about point A:
∑τ = Iα
-mg (L/2) + Rb x = 0
-(5 kg) (10 m/s²) (0.75 m) + Rb (0.70 m) = 0
Rb = 53.6 N
Sum of forces in the y direction:
∑F = ma
Ra + Rb − mg = 0
Ra = mg − Rb
Ra = (5 kg) (10 m/s²) − 53.6 N
Ra = -3.6 N