Vector AdditionChapter 3 – Part 1

Vectors represent magnitude and direction

• Vectors vs. scalars?

• Vectors can be added graphically

A student walks from his house to his friend’s house (a), then from

his friend’s house to the school (b). The student’s resultant

displacement (c) can be found by using a ruler and a protractor.

Vectors represent magnitude and direction

• To add vectors – draw “tip to tail” (these are the component vectors)

• Resultant vector is sum (think “as the crow flies”

A student walks from his house to his friend’s house (a), then from

his friend’s house to the school (b). The student’s resultant

displacement (c) can be found by using a ruler and a protractor.

Vectors can be manipulated graphically

• To add vectors - pythagorean theorem

• Vector resolution – use trig functions

The Pythagorean Theorem

• Use the Pythagorean theorem to find the magnitude of the resultant vector.

Trigonometric Functions

• Use trig functions to find the magnitude of any vector.

Resolving Vectors into Components

Consider an airplane flying at 95 km/h.

• Hypotenuse = resultant vector

• Adjacent leg = x component

• Opposite leg = y component