# Density EQ: Why do some objects float and other objects sink?

## Presentation on theme: "Density EQ: Why do some objects float and other objects sink?"— Presentation transcript:

Density EQ: Why do some objects float and other objects sink?

What is density?. Density is a comparison of how much matter there is in a certain amount of space. Each substance has a specific density. Density can be used to identify a substance SubstanceDensity (at 20°C Wood0.70 g/cm 3 Corn oil0.92 g/cm 3 Water1.00 g/cm 3 Rubber1.34 g/cm 3 Copper8.80 g/cm 3

Which one is more dense? Demonstration: People in a square How about this: Which square is more dense?

Which one is more dense? Now which one is more dense?

What is density? ALWAYS REMEMBER UNITS!

Let’s try a density problem together Frank has a paper clip. It has a mass of 9 g and a volume of 3 cm 3. What is its density?  9 g ÷ 3 cm 3 = 3 g/cm 3 Frank also has an eraser. It has a mass of 3 g, and a volume of 1 cm 3. What is its density?  3 g ÷ 1 cm 3 = 3 g/cm 3

Work on these problems with your neighbor. Jack has a rock. The rock has a mass of 6 g and a volume of 3 cm 3. What is the density of the rock? Jill has a gel pen. The gel pen has a mass of 8 g and a volume of 2 cm 3. What is the density of the rock?

Now, try these on your own. Alicia has a watch. It has a mass of 4 g and a volume of 2 cm 3. What is the density of the watch? Mia has a wallet. It has a mass of 15 g and a volume of 5 cm 3. What is the density of the wallet?

What if you already know density? Use the density triangle, or DMV, to solve for the missing part. D = M÷V V = M÷D M = D×V

Liquid Layers – Try with your neighbor Which liquid has the highest density? Which liquid has the lowest density? Which liquid has the middle density?

Liquid Layers – Try on your own! Imagine that the liquids on the right have the following densities:  15 g/ml 10 g/ml  3 g/ml 9 g/ml  7 g/ml 12 g/ml Match the colors to the correct densities. 3 g/ml 7 g/ml 9 g/ml 10 g/ml 12 g/ml 15 g/ml

Super Scientist Question of the Day Jake has a book, a ruler, and a balance. How can Jake find the density of the book with the tools he has?

Download ppt "Density EQ: Why do some objects float and other objects sink?"

Similar presentations