4.5 Measuring Matter: Mass, Weight, and Volume Text pages 113-115
4.5 Overview Key idea Vocabulary Explain the concept of force Determine the density of a variety of substances Mass Weight Volume Meniscus Displacement
What is matter Something that has a mass and volume If it is not matter… it is energy
What is the difference between mass and weight?
Mass = the amount of matter in an object grams, g; milligrams, mg; kilograms, kg Mass is always the same
Weight= the force of gravity pulling on the object Weight is different depending on the planet! Gravity keeps things on the ground, it is the Earths pull The pull of gravity is measured in Newtons, N
If I travelled to the moon, would I lose weight? YES, because the moon has a different gravity/pull than on Earth… you are pull down on less on the Moon! 9.8 m/s2 = Earths gravitational pull 1.6 m/s2 = Moons gravitational pull Your mass will always be the same…. You will always have the same amount of stuff inside of you!!
Does your bathroom sale measure mass or weight? It measures the Earth’s pull on your body!
What is Volume The amount of “space” that an object takes up = outside Capacity= The amount of space in a substance (like a tube, juice container, tube of tooth paste) = inside Meters cubed, m3; centimeters cubed, cm3; liters, L; millilitres, mL
Volume is measured in many different ways Liquids: Measured by observing how much of a container they fill up Beaker, graduated cylinders (GC), measuring cup Units = mL, L, kL
Regular shaped objects (straight edges, cubes, rectangles) Use a ruler Volume = L x W x H Units = m3, cm3
(volume of water + object) – (volume of water) Small irregular shaped objects (rocks…) Displacement: Choose a container that the object can fit in Fill up with water till half full Record the volume Add the object Record the volume again Subtract the two volumes = volume of object This is the amount of space the object took up! Volume of object = (volume of water + object) – (volume of water) * larger number * smaller number
Large irregular shaped objects Overflow method Need an overflow can and a GC Fill overflow can till water starts to come out of spout, place GC under overflow spout Add object to over flow container Record how much water is in the GC The water that overflowed into the GC = the amount of space the object took up
Which method is which?
Which method would you use?
If you travelled to the moon, would my volume change? NO, you will still take up the same amount of space….