Respostas

2013-09-07T18:05:28-03:00
Fr² = F1² + F2² + 2 * F1*F2 * cos(alpha)

Fr² = 10² + 20² + 2*10*20 * cos (45°)

Fr² = 100 + 400 + 400V2/2

Fr² = 500 + 200V2

adotando V2 = 1,4

Fr² = 500 + 280

Fr²= 780

Fr = V780

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Fr ~= 28N ( Arredondando) 
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