1. Chapter 4-1 The Foundations of Physical Science
MOTION
Chapter 4-1
The Foundations of Physical Science

2. Position, Speed, and Velocity
Position- a variable that tells location relative to an origin
Origin- a place where the position has been given a value of zero
Speed / Velocity - describes how quickly an object moves
Calculated by dividing the distance traveled by the time it takes

3. FORMULA

5. Average Speed and Instantaneous Speed
Average speed - the total distance divided by the total time for the trip
On a real trip, your car will slow down and speed up. This is why it is called average speed
Instantaneous speed - the actual speed of an a moving object ay any moment
Your car’s speedometer shows your instantaneous
speed. It is the actual speed of your car at any moment

6. LET’S SOLVE A PROBLEM
How far do you go if you drive for two hours at a speed of 100 km/h?
Looking for:
distance
Given:
speed = 100 km/h time = 2 h
Formula:
d = vt
Solution:
d = 100 km/h x 2 h = 200 km

7. Vectors and Velocity
How can you tell the difference between one meter in front of you and one meter behind you?
The variable of distance is not the answer
The distance between two point can only be positive (or zero)
You can not have a negative distance

8. Position and Vectors The answer is to use position
Position allows for positive and negative numbers
Position is an example of a kind of variable called a vector
A vector is a variable that tells you a direction as well as an amount

9. Position and Vectors
Positive numbers are for positions to the right of the origin and negative numbers are for positions to the left the origin.

10. Velocity
Like position, motion can go right, left, up, down, forward, and backward
We use the term velocity to mean speed with direction
Positive velocity is moving to the right or forward
Velocity is negative when moving to the left or backward

11. Velocity VS Speed
In regular conversation, you may use speed and velocity to mean the same thing
In science, they are related but DIFFERENT

12. Velocity VS Speed
Speed can only have a positive value that tells how far you move per unit of time
Tells how quickly you are moving

13. Velocity VS Speed Velocity tells both speed and direction
The positive or negative sign tells you if you are going forward or backwards
+ = forward
- = backward