Respostas

2013-08-03T03:37:28-03:00
Fr² = F1² + F2² + 2*F1*F2 * cos alpha

Fr² = 100 + 100 + 2*10*10* cos60°

Fr² = 100 + 100 + 200 * 1/2

Fr²= 100 + 100 + 100

Fr² = 300

Fr = Raiz de 300

Fr = 10V3 N

Arredondando V3 para 1,7 temos

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Fr = 17 N
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