1. Gravity

2. Sir Isaac Newton was the first person to seriously study gravity.
Gravity is a force that attracts all objects to each other.
Gravity is measured in Newtons.

3. Law of Universal Gravitation
Strength of gravity depends on:
Masses of the objects (as mass increases, force increases)
Distance between the objects (as distance increases, force decreases)
Acceleration due to gravity (free-fall acceleration) = 9.8 m/s/s OR 9.8 m/s2

4. Mass Vs. Weight Mass = amount of matter in an object
Weight = force of gravity on an object, dependent upon location, influences shape of living things (“form fits function”)

5. Weight and Location

6. All objects are affected by gravity!
-Gravitational force increases as mass increases!
- An elephant is more massive than a cat. The gravity between it and Earth is larger than between the cat and the Earth, so it’s harder to pick up the elephant and overcome that force.

7. -Gravitational force decreases as distance increases.
- If the distance between 2 objects is doubles the gravitational force between them decreases to one-fourth.
- If it triples, the force decreases to one-ninth, etc.

8. Free fall
The motion of a body when only the force of gravity is acting upon it.
Free-fall acceleration is 9.8 m/s/s.
Constant (because near the surface of the Earth the other factors involved are constant)

9. Air resistance Can balance weight.
Acts on objects moving through the atmosphere (along with gravity.)

10. Terminal velocity
Constant velocity of a falling object when the force of air resistance is equal to weight and opposite in direction.

11. Projectile Motion
Curved path followed by an object that is thrown, launched, etc.
Curved because of having both a horizontal and vertical component.