The length of this side right over here is five so I could say the magnitude of A is equal to five. Velocityaccelerationforce and many other things are vectors.
There is one representation of a vector that is special in some way. In other words, the point where we apply the force does not change the force itself.
We can add two vectors by joining them head-to-tail: And it doesn't matter which order we add them, we get the same result: Example: A plane is flying along, pointing North, but there is a wind coming from the North-West. Once again we just divide by the magnitude, magnitude of our vector.
A vector has magnitude size and direction: The length of the line shows its magnitude and the arrowhead points in the direction. Because we square all the components the only way we can get zero out of the formula was for the components to be zero in the first place.
Note that there is very little difference between the two dimensional and three dimensional formulas above. If you watched the plane from the ground it would seem to be slipping sideways a little.