Vector Sum: Component Method

A has a length 3.76 cm and is at an angle of 34.5 degrees above the positive x-direction. B has a length 4.53 cm and is at an angle of 34.1 degrees above the negative x-direction. What is their sum?

If C = A + B, then:    Cx = Ax + Bx     Cy = Ay + By.

The resultant vector is: C = -0.65 cm + 4.67 cm

Or, express the resultant in terms of its magnitude and direction.

C2 = Cx2 + Cy2 = 0.652 + 4.672  or   C = 4.72 cm.
tan(θ) =
4.67
-0.65
This gives θ = 97.9 degrees.

The resultant vector has magnitude 4.72 cm and is rotated 97.9 counterclockwise from the +x direction.