Physicists call the vector sum the “resultant vector.” Usually, we prefer to call it “the resultant” or, as in
our diagram, “ R .”
How to add vectors:
- Line them up head-to-tail.
- Draw a vector that connects the tail of the first arrow to the head of the last arrow.
Vector Components, Revisited
Breaking a vector into its components will make many problems simpler. Here’s an example:
To add the vectors in Figure 9.4a , all you have to do is add their x - and y -components. The sum of the x
-components is 3 + (−2) = 1 units. The sum of the y -components is 1 + 2 = 3 units. The resultant vector,
therefore, has an x -component of +1 units and a y -component of +3 units. See Figure 9.4b .
Figure 9.4a Adding vectors.Figure 9.4b Final sum of vectors.