Find the resultant vectors if the given changes are made in the indicated examples of this section.

In Example 2, find the resultant if θ_A is changed to 0°.

Data from Example 2

Find the resultant of two vectors A and B such that A 120̅0, θ_A = 270.0° , B = 1750, θ_B =  115.0°.

First, place the vectors on a coordinate system with the tail of each at the origin as shown in Fig. 9.22(a). Then resolve each vector into its x- and y-components, as shown in Fig. 9.22(b) and as calculated below. (Note that A is vertical and has no horizontal component.) Next, the components are combined, as in Fig. 9.22(c) and as calculated. Finally, the magnitude of the resultant and the angle (to determine the direction), as shown in Fig. 9.22(d), are calculated. The reference angle is found first and then used to determine the standard position angle θ.

By 115.0 $1. B (a) B 270.0 Fig. 9.22 R Ry (c) R Oref 0 (d) X