1. MASS, VOLUME, DENSITY, WEIGHT, & GRAVITY

2. Mass, Volume, Density, & Weight Mass – the amount of matter in an object Volume – the amount of space an object takes up Density – the amount of mass per unit of volume (D=M/V) Weight– the amount of force of gravity on an object

3. GRAVITY Gravity gives weight to objects and causes them to fall to the ground when dropped. Gravity is responsible for keeping the Earth and the other planets in their orbits around the sun and for keeping the moon in its orbit around the Earth. As objects move farther apart, the gravitational pull between them gets weaker. The gravitational force felt on a planet or moon depends on it’s size and mass. As a result the gravity on the moon is 1/6 that of Earth. Larger size and mass means more gravity so you would weigh more on a large planet with a mass.

4. Space Shuttle Why do objects inside the space shuttle float? Once the shuttle is launched into space and leaves Earth’s atmosphere, the gravity of the Earth has less effect on the objects so they float.

5. Earth vs. Moon The gravitational force felt on a planet or moon depends on it’s size and mass. As a result the gravity on the moon is 1/6 that of Earth. To find the weight of an object on the moon, divide its weight on Earth by 6. To find the weight of an object on Earth, multiply its weight on the moon by 6.

6. MASS Units of measurement – grams/kilograms Mass is measured using a balance. Your mass will always stay the same, but your weight can change depending on the amount of gravity.

7. Volume Unit of measurement – liters/milliliters You can find an regular shaped object’s volume by multiplying length by width by height. (L x W x H) If the object has an odd shape such as a rock or shell, then you can find an object’s volume with water displacement.

8. WEIGHT Unit of measurement – ounces and pounds Weight is measured using a scale. Weight is affected by gravity. The amount of gravity on a planet or moon affects the weight of objects on the surface.

9. Review Questions 1.What is mass? 2.What is weight? 3.What is volume? 4.How can you find the volume of an irregularly shaped object? 5.What is the formula for finding density? 6.What is density? 7.How are mass and weight different? Think about being on the moon versus being on Earth.