Vectors & Scalars9/10/2015

Scalars

Scalars are quantities or measurements with no direction.

Can you think of an example?

Examples

Almost all base units are scalars

Time, Length, Mass ect.

What are vectors?

Vectors represent a value with magnitude and direction

Today we will use vectors to describe the motion of your bodies around the school

Creating a Vector

To create a vector we need a magnitude and direction

An example could be saying you travelled 2 miles east

Example

Mr. Peterson decided to visit a relative in Duluth. He travelled 150 miles west

How can we draw a vector to describe Mr. Peterson’s motion

Adding Vectors

To add vectors we use the Tip to Tail method. When you draw a vector from the beginning of the first vector to the tip of the final vector this gives you a resultant vector

This means we add the tip of the first vector to the tail of the second

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=How would we find the resultant vector?

Example

Leslie decided to go get ice cream she travels 2 miles west. She then wants to bring one ice cream cone to her grandmother who lives 1 mile west. What is Leslie’s resultant vector?

Adding opposite vectors

Some vectors go different directions.

We still add these using the Tip to Tail method. The resultant vector then starts at the beginning of vector one and goes to the tip of vector two

Example: Noah drove 50 miles East. However, he left his phone at a gas station and had to drive 20 miles East to pick it up. What was Noah’s resultant vector?

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Example

John drives to Duluth which is 150 miles North. He then drives from Duluth to Superior which is 2 miles South. What is John’s resultant vector?