Do Now

1
Do Now

• In your notebook, answer the following question
  in complete sentences
• What is the difference between mass and weight?

2
Mass vs. Weight

• Mass
• The amount of matter in an object
• Weight
• The force of gravity acting on an object
• The difference??
• GRAVITY

3
Gravity

• What forces act upon celestial bodies?

4
Objectives

• Define the term gravity.
• Compare and contrast mass and weight
• Describe the factors that affect gravity

5
What is Gravity?

• Gravity is the attractive force between two
  objects
• Gravitys magnitude depends on
• Mass of objects involved
• Distance between objects

6
Newtons Law of Gravitation

• F Gravitational Force
• G Universal Gravitation Constant
  6.6726x10-11m3/(kgs2)
• m1 mass of first object
• m2 mass of second object
• r distance between centers of objects

7
Gravity in Space
Body Multiple ofEarth gravity m/s2
Sun 27.90 274.1
Mercury 0.3770 3.703
Venus 0.9032 8.872
Earth 1 9.8226
Moon 0.1655 1.625
Mars 0.3895 3.728
Jupiter 2.640 25.93
Saturn 1.139 11.19
Uranus 0.917 9.01
Neptune 1.148 11.28
Pluto 0.0621 0.610