Ch 3 Vectors

Check out Vector Fundamentals from The Physics Classroom

The most important aspect of understanding vectors is that they have a direction that must be taken into consideration when working with them mathematically. Vectors that point 180 degrees from each other would have opposite signs (+ and -). Vectors that point the same direction should have the same sign. It is up to us to decide what direction is positive or negative. The convention for up and down is positive up and negative down.

vector-V2.gif Check out Hyperphysics Vector Interactive

Vectors that are at an angle can be broken down into component parts, typically into horizontal X and vertical Y components. Simple trig functions will be used to determine the X and Y component values.
Conversely, X and Y parts can be turned into a single "Resultant" vector (the hypotenuse if you can picture a right triangle). Use the Pythagorean Theorem to find the hypotenuse (Resultant) of two X and Y vectors acting together.

Vector addition:

Vectors can be added together to find a resultant vector. An infinite number of vectors can be added to produce one resultant! The simplest method is to put two tails together and make a parallelogram out of them and draw the diagonal resultant. V + W is shown below:
Another method is toput vectors tip to tail and draw the result between the start and finish of the vectors. This method is VERY useful for more than two vectors being added!