12.2: Adding Vectors
- Page ID
- 119309
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Vectors are useful for representing quantities like force and acceleration because we can add them up without having to think explicitly about direction.
As an example, suppose we have two vectors representing forces:
>> A = [2, 4];
>> B = [2, -2];A represents a force pulling northeast; B represents a force pulling southeast, as shown in Figure 12.1:
Figure 12.1: The sum of two forces represented by vectors
To compute the sum of these forces, all we have to do is add the vectors:
>> A + B
ans = 4 2Later in the chapter, we’ll use vector addition to add accelerations due to different forces acting on a baseball.