ARCHIMEDES PRINCIPLE& BUOYANCY

(plus, a little review on density)

Buoyancy Buoyancy is an upward force acting on

an object placed in a fluid.

(don’t worry about this, we will learn more about it when we get to forces in the physics unit)

Archimedes Principle When an object is immersed in water, it

feels lighter. In a cylinder filled with water, the action of inserting a mass in the liquid causes it to displace upward.

Archimedes Principle In 212 B.C., the Greek scientist

Archimedes discovered the following principle: “The buoyant force acting on an object is equal to the mass of the displaced fluid.” This became known as: Archimede's principle.

Now, time for some review! What are the units used for mass?

What are the units used for the volume of a fluid? (how can you help yourself remember this?)

What are the units used for the volume of a solid? (how can you help yourself remember this?)

What are the units used for the density of a solid?

What are the units used for the density of a liquid?

Based on the data, what should you solve for? And what is the answer? Volume = 10ml, Mass= 5g Mass= 25g, Volume= 5ml Volume= 15, Density= 2g/cm3

Density= 25g/ml, Mass= 50g Mass= 100g, Volume= 25cm3

Volume = 40ml, Mass= 10g

Graphing? How do we set up a graph for density?

Let’s do one together!

Mass Volume

5 grams 10 ml

10 grams 20 ml

15 grams 30 ml

20 grams 40 ml

25 grams 50 ml

30 grams 60 ml

35 grams 70 ml

Cleaning Fluid “X”

What is the densityOf cleaning fluid X?