Question

Solve the resultant and direction of the forces given by component and closed polygon method force 1= 100 grams, due east force 2= 120 grams 30° south of west force 3= 80 grams, 45° South of East?

Answer 1

$F_x=F_1-F_3\cos30°+F_3\cos45°=52.6,$

$F_y=F_2\sin30°+F_3\sin45°=116.6,$

$F=\sqrt{F_x^2+F_y^2}=127.9,$

$\alpha=\arctan\frac{ F_y }{F_x}=65.7°$ South of East.