1. 13th Bell Ringer
If a person is being rolled in a wheel barrow by another person, list all the types of frictions occurring.
And, how could they make their friction greater?

2. Lesson Essential Question
Concept: Basic Forces
LEQ: How does gravity affect an object?

3. Vocabulary Freefall Air Resistance Terminal Velocity Weight
(Acceleration due to) Gravity

4. Challenge
Find two objects in this room (objects that will not break) that will fall and hit the floor or table at different times.
Your objects must be released
at the same time
And at the same height

5. Gravity Brainpop
You have a question and answer sheet to go along with the following video

6. Graphic Organizer
We will watch the following video twice and then fill in our graphic organizer together during the second viewing

7. Weight as the Force of Gravity

8. Recall A force is a push or a pull on an object.
A force is the product of an object’s mass and its acceleration.
F=ma

9. Gravity Earth’s Gravity = 9.8m/s2
Gravity is the force of attraction between any two objects.
When an object falls, it is pulled toward another object by the larger object’s gravitational force.
The pull of gravity causes the object to accelerate toward the source of the gravitational force.

10. Weight aka the Force of Gravity
Weight is the pull of gravity on a particular object.
The force of gravity (aka weight) is the product of the mass of an object and its acceleration.
Find the formula:
Like all forces, the unit for weight is Newtons.

11. Calculating the Force of Gravity
A notebook at Wal-mart has a mass of 10 kg. If this Wal-mart is located on Earth, what is the weight of the notebook?
Step 1: Find the information given in the problem.
Step 2: Write the formula
Step 3: Substitute the information from the problem into the formula
Step 4: Solve for the unknown variable

12. Example 2
An astronaut discovers a 30 kg moon rock while exploring. When he drops the rock, it accelerates toward the surface of the moon at 3 m/s2.
What is the weight of this moon rock while on the moon?
What will be the weight of this moon rock when it is moved to Earth?
Fg=(30 kg)(3m/s2)
Fg=90 N
Fg=(30 kg)(9.8m/s2)
Fg=294 N

13. Mass vs. Weight Weight Mass The quantity of matter in the object
Cannot be changed without a piece being lost or gained
Does not change based on gravity
The force of gravity on an object’s mass
Changes if the gravity pulling on the object changes OR is the amount of matter changes

14. What is happening to mass and weight?
An astronaut goes from Florida to the moon
A piece of the space shuttle falls off while exiting our atmosphere
Climbing to the top of Mt. Everest
Returning to Texas after visiting Mars
Mass: No change
Weight: Decreases
Mass: Decreases
Weight: Decreases
Mass: No change
Weight: No change
Mass: No change
Weight: Increases