how do i find magnitude and direction of resultant force! Giving medals for clear instructions step by step! also using parallelogram law and triangle rule!

Question

adunb8 · Answer

attachment

dumbcow · Answer

resultant force is found by adding the x,y components of each of the other forces

$$R_x = 120 \cos \alpha + 40 \cos(180 - \beta)$$
$$R_y= 120 \sin \alpha + 40 \sin(180 - \beta)$$
magnitude
$$|R| = \sqrt{R_x ^{2} +R_y ^{2}}$$
direction
$$\tan \theta = \frac{R_y}{R_x}$$

adunb8 · Answer

@dumbcow  why did you subtract 180-B ?

adunb8 · Answer

for Rx and Ry 40sin(180-b)??

adunb8 · Answer

im not understanding how you got Rx and Ry ...

dumbcow · Answer

crap yeah those angles are wrong....anyway you want the angle the force makes with the pos x-axis

dumbcow · Answer

for 120 lb force  --- 180 +a

for 40 lb force   ---- 360 - b

adunb8 · Answer

um.. im not quite getting it. but ok thanks

dumbcow · Answer

maybe this will help
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