Monday Fill out planner WU: Which weighs more, a pound of feathers or a pound of lead. Explain. Update Journal

Monday 02/13/12 Fill out planner WU: 1) In your own words, what is density? 2) A volleyball and a bowling ball have roughly the same volume but very different weights. Why? Update Journal

Density 1. Define mass? 2. Define volume? 3. Give an example of 2 objects of different densities and use them to explain what density is. 4. Why does changing the shape of an object have no effect on the density of that object? 5. Aluminum is used to make airplanes. Cast iron is used to make weightlifting equipment. Explain why the densities of these metals make them useful for these purposes? 6. Why does an air bubble rise to the surface of a glass of water? How much mass in a given space The amount of matter in an object (measured in grams or kilograms How much space an object takes up (measure in liters or milliliters or cm 3 A basketball and a bowling ball each take up about the same space but because the bowling ball has more molecules, it weighs more Because the space between molecules does not change (mass per unit volume does not change) Airplanes need a “light” material to liftoff (Aluminum has low density) Weights for weight lifting need to be “heavy” (Cast Iron is very dense) Bubble is less dense than water so it rises

a) d = V = 950 mL M = 95 g b) d = 3 g/mL V = 100 mL M = c) d = 0.5 g/cm 3 V = M = 20 g D = m v D = 95g 950ml D =.1 g ml m = d x v M = 3 g x 100ml ml M = 300 g V = m d V = 20g.5 g/cm 3 D = 40 cm 3

To Do: Worksheet