1. Gravity- I’m Attracted to You
Earth Space

2. Gravity
The force of attraction that exists between all matter in the universe.
Key word is matter
Matter is the stuff you are and everything else is made of
It takes a lot of mass for the gravity to be noticeable.
Like planetary mass

3. Law of Gravity
The force of attraction between any two objects depends on their masses and the distances between them.
The bigger the object, the more gravity it has
The closer an object is to something the stronger the pull.

4. Mass Mass is how much matter is in something.
It is measured using grams and kilograms
It is NOT the same as weight

5. Distance
Gravity’s force depends on how close the object is to something.
As an object gets further away, the force of gravity on that object decreases
Inverse square law
As the distance increases the gravity decreases exponentially
Class demonstration

6. 1
Gravitational force =
Distance squared 1
G force = d2

7. Weight, Mass, and Gravity
Weight and Mass are not the same thing!!!
The are related though
Weight is your mass being pulled down by gravity
Gravity on earth pulls us down at 9.8 m/s2

8. Weight, Mass, and Gravity
How much matter you are made of
Does not change depending location
It is the same if you are on earth or in space or on the moon
Weight
The relationship between mass and gravity
Changes depending on location
Is different on earth and the moon and space

9. In the absence of air resistance, all things will fall toward the earth at the same velocity
Weight = mass x free-fall acceleration
w= m g

10. Find Your Mass
We can find out how much mass we have by using the previous formula
W = mg
Weight is in Newtons, so convert your lbs to N.
Multiply lbs times 4.448
Then divide by gravity

11. Gravity on Earth Gravity pulls us down toward the center of the earth.
At different parts of the earth there is more matter between the surface and the center.
The Poles are flatter and the equator bulges
The bulge means there is more gravity at the equator
People weigh more at the equator than the poles.

12. Gravity & the Moon
Newton observed the Moon’s motion and realized that its direction changes because of the gravitational attraction of Earth
The Moon is constantly falling toward Earth
If no gravity, the Moon would continue to move in a straight line and would not orbit Earth
The same is true of the planets and their moons, stars, and all orbiting bodies throughout the universe.