Letra a)
Temos que:
Força resultante (Fr)
Fr² = F1² + F2² + 2 * F1*F2 * cos(alpha)
Fr² = 1² + V2² + 2*1*V2 * V2/2
Fr² = 1 + 2 + 2*V2² / 2
Fr² = 3 + 2
Fr² = 5
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Fr = [tex] \sqrt{5} [/tex] N
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Letra B)
Fr² = F1² + F2² + 2*F1*F2*cos(alpha)
Fr² = V2² + V2² + 2*V2*V2 * cos(90°)
Fr² = 2 + 2 + 2V2² * 0
Fr² = 2 + 2
Fr² = 4
Fr = [tex] \sqrt{4} [/tex]
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Fr = 2N
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