Which weighs more, a pound of feathers, or a pound of bricks? Measuring Matter Which weighs more, a pound of feathers, or a pound of bricks?

Weight or Mass? Weight is a measure of the force of gravity on you Mass is measurement of how much matter is in an object An object’s weight changes from Earth to the moon or other planets, but the mass stays the same. REASON? Weight is a measure of the force of gravity on you, on the moon, gravity is much weaker.

Measuring Mass Uses International System of Units (SI) kg = kilogram is a unit of mass g = gram 1000 g = 1 kg Examples: Nickel = 5 g baseball = 150 g glass of water =200g

Measuring Volume Volume is…… the amount of space that matter occupies Regular objects Volume = length x width x height A rectangle has a length= 9 cm height= 5 cm width= 4.2 cm Then, 9 x 5 x 4.2 =189 cm3 (cubic centimeters) W H L

Measuring Volume Irregular Objects Use water displacement with a graduated cylinder Odd shaped objects like: ball, egg, rock STEPS: Fill graduated cylinder with water Measure mL of water at the meniscus and write down amount Place irregular object in graduated cylinder Measure mL of water at the meniscus again Find the difference between the 2 water levels by subtraction Record the answer in volume mL

Other units of measurement Measuring liquids liter (L) milliliter (mL) 1000 mL = 1 L Measuring Distances kilometer (km) meter (m) centimeter (cm) millimeter (mm) 10mm = 1 cm 100cm = 1 m 1000m = 1 km

Density Density is the measurement of how much mass is contained in a given substance Density = mass divided by volume Things that float on water are less dense than water. Less dense in water = float Things that sink in water are more dense than water. More dense in water = sink Things that neither float or sink, stay level, have the same density Same density = level