Mass Density • Mass density is a measure of mass per volume High Density • Formula sheet M = VDm Rearrange to solve Now need M and V Low Density

Mass Density: Mass per Volume • Mass measured in units such as – US Customary: ounces (oz) or pounds (lb) – SI: grams (g), kilograms (kg) • Volume measured in units such as – US Customary: Cubic inches or feet (in. 3 or ft 3) – SI: Cubic centimeter or meter (cm 3 or m 3) Material Mass Density (kgm-3) Atmosphere (Earth @ Sea Level) 1. 2 Water (Pure) 1, 000 Water (Sea) 1, 030 Aluminum 2, 700 Steel (1018) 7, 833 Lead 11, 340

Sources of Mass and Volume Measurement • Mass – Typically measured directly using a scale • Volume – Calculate based on geometry and dimension measurements – Indirect measurement using water displacement or 3 D scanner

Volume: Calculation • Some object volumes can be calculated • What is the volume formula for each object?

Volume: Indirect Measure • Volume of an irregular object can be determined indirectly with fluid displacement Level Elevates

Volume: Indirect Measure • • Record water level with only water Add samples Record new level Difference is sample volume Volume Change Read level here Meniscus shape is exagerated for clarity

Example • What is the density of a 1. 12 in. sphere of titanium that weighs 0. 96 lb • What volume of water would it displace?