Vectors

Vectors: magnitude and direction

Practice

Scalar Multiplication

Sum of vectors Must add head to tail A B C Example: + =

Vector Subtraction u v - v u - v - v u

Name the resultant This means sum Start at the dot Follow “roads” u v w u v -w u u + v – w (resultant) Had to flip w to follow road

Dot Product

Components (aka triangles) use SOH CAH TOA X Y 30 ̊ 15 - Be careful what quadrant X and y both positive X Y 30 ̊ 15 X positive, y negative

Find the resultant: draw the vectors given and answer is the path they make A C B

Find the resultant of forces ̊ ̊ resultant Have to move to add, Use law of cos or sin

Vector VS Scalar Vector is 2 numbers Scalar is 1 numbers 3 = vector ||v||= scalar