2: Vectors

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2.1: A Vector Primer
A vector is a quantity that possesses magnitude and direction. As an example, let’s say I roundhouse kicked you in the head. The magnitude of the force and the angle at which I kicked you would be a vector.
2.2: Quadrants
A quadrant is a circle cut into four parts.
2.3: Polar vs. Rectangular Form
When dealing with vectors, there are two ways of expressing them. Up to this point, we have used a magnitude and a direction such as 30 V @ 67°. This is what is known as the polar form. It is more often the form that we like to express vectors in.
2.4: Vector Addition
When adding vectors, we have to find some common ground. This is why we focus on the X and Y coordinates. Each vector can be broken down into X and Y coordinates. This allows us to find some common ground as the X coordinates are heading in the same direction and the Y coordinates are heading in the same direction.

Thumbnail: Vector in a Cartesian coordinate system. (CC BY-SA 4.0 unported; Acdx).