2. A force is a push or a pull
Simple statement:
A force is a push or a pull

3. Forces add like vectors
Forces are vectors
Forces add like vectors

4. Four Fundamental Forces
Gravity
Electromagnetic
Strong Nuclear Force
Weak Nuclear Force

5. Newton’s First Law of Motion: Book:
An object at rest remains at rest as long as no net force acts on it.
An object moving with constant velocity continues to move with the same speed and in the same direction as long as no net force acts on it.

6. Newton’s First Law of Motion: Book:
An object at rest remains at rest as long as no net force acts on it.
An object moving with constant velocity continues to move with the same speed and in the same direction as long as no net force acts on it.
Mine (better!):
The velocity of an object will not change unless a net external force acts on it.

7. Newton’s First Law of Motion: Book:
An object at rest remains at rest as long as no net force acts on it.
An object moving with constant velocity continues to move with the same speed and in the same direction as long as no net force acts on it.
Mine (better!):
The velocity of an object will not change unless a net external force acts on it.
This is commonly known as “inertia”

8. A demonstration of inertia

9. A demonstration of inertia
VIDEO

10. This was not always so obvious:
Do moving things on Earth generally keep on moving?

11. This was not always so obvious:
Do moving things on Earth generally keep on moving?
The ancient Greeks concluded that the natural state of motion of all objects is rest.
But then, they concluded lots of things that are wrong…