BALANCE IT OUT MEASURING MASS MASS Definition: Definition: Mass is a measure of how much Mass is a measure of how much matter something contains matter something contains Mass and weight are often confused. They are two different concepts. They do not mean the same thing. MASS VS. WEIGHT MASS The measure of how much matter is in an item. The measure of how much matter is in an item. WEIGHT The measure of how strongly gravity is pulling downward on an object. MASS VS. WEIGHT MASS Measured using a balance Triple Beam Balance Pan Balance WEIGHT Measured using a spring scale MASS VS. WEIGHT MASS Units of measurement = Kilograms, Grams or Milligrams WEIGHT Units of measurement = Newtons MASS VS. WEIGHT If you traveled to the moon your mass would stay the same as on Earth, BUT, your weight would be less. The moon is smaller than the Earth (smaller mass), therefore, the force of gravity is less on the moon than on the Earth. Since weight is a factor of the force of gravity, and there is less gravity on the moon, then, your weight would be less on the moon. Why does weight change, but not mass? Why is mass always constant? Mass is the amount of matter that an object contains. An object will contain the same amount of matter no matter where you move it to. You are still made up of the same amount of stuff or matter, therefore, your mass would not change. MASS VS. WEIGHT A KEY TO WHICH UNITS TO USE FOR MEASURING MASS KILOGRAMS KILOGRAMS Used for items that would weigh 1000 grams or more Used for items that would weigh 1000 grams or more GRAMS GRAMS Used for items that would weigh up to 999 grams which would be anything you could measure on an normal balance scale Used for items that would weigh up to 999 grams which would be anything you could measure on an normal balance scale MILLIGRAMS MILLIGRAMS Used for items that weigh less than one gram Used for items that weigh less than one gram BASIC CONVERSIONS 1 kilogram (kg) = 1000 grams (g) 1 gram (g) = 1000 milligrams (mg) FINDING MASS ON A TRIPLE BEAM BALANCE A triple-beam balance works by comparing the mass of the object you are measuring to a known mass You use the known masses of the 1 gram, 10 gram, and 100 gram riders. FINDING MASS ON A TRIPLE BEAM BALANCE When you use a triple-beam balance, you: 1.Place the object on the pan 2.Shift the riders on the beams until them balance the mass of the object Start with the large rider (increments of 100) Next, the medium sized rider (increments of 10) Lastly, the small rider (increments of 1) What is the mass of the turtle? grams