Archimedes and the Crown

A Genius in the TubA Genius in the Tub

Who is Archimedes?

Archimedes was a Greek philosopher and Archimedes was a Greek philosopher and mathematicianmathematician

Archimedes

(287-212 B.C.)(287-212 B.C.)

he lived more than 2,000 years agohe lived more than 2,000 years ago

• he is still known as he is still known as one of the greatestone of the greatest physical physical scientists of all time.scientists of all time.

Why do we still talk about him?

This is a story about one of his most famous discoveries.

It is so famous it is called:It is so famous it is called:

The Archimedes The Archimedes PrinciplePrinciple

Archimedes lived more than 2000 years ago Archimedes lived more than 2000 years ago in a Greek city called Syracuse. in a Greek city called Syracuse.

There he is: Archimedes

• He was very good at inventing things and figuring He was very good at inventing things and figuring out how things work.out how things work.

• Archimedes was so smart that the king of the roots Archimedes was so smart that the king of the roots crew, Tubby, needed his help many times.crew, Tubby, needed his help many times.

• Once King Tubbby had a Once King Tubbby had a goldsmithgoldsmith make make him a new crown.him a new crown.

• He gave the goldsmith lots of gold to make He gave the goldsmith lots of gold to make a big beautiful crown.a big beautiful crown.

• The goldsmith made King Tubby a crown The goldsmith made King Tubby a crown shaped like a beautiful ring of gold leaves, shaped like a beautiful ring of gold leaves, just like the Korean Bird Feather Crownjust like the Korean Bird Feather Crown

• But King Tubby told Archimedes that he But King Tubby told Archimedes that he was worried. He did not trust the goldsmith was worried. He did not trust the goldsmith who lived strictly for the money.who lived strictly for the money.

The goldsmith may want to keep some of The goldsmith may want to keep some of the gold for himself and mix something else the gold for himself and mix something else with the rest of the gold to trick the king with the rest of the gold to trick the king and pocket the extra gold. and pocket the extra gold.

King Tubby had a beautiful new gold King Tubby had a beautiful new gold crown, but was it really all gold? He crown, but was it really all gold? He wondered and wondered… wondered and wondered…

He could find out by having the crown He could find out by having the crown melted to see what it was made of, but then melted to see what it was made of, but then he would have to remake the crown. he would have to remake the crown.

And if he paid the And if he paid the goldsmith again would goldsmith again would he steal some of the gold the second he steal some of the gold the second time he made the crown? Who knows.time he made the crown? Who knows.

The king knew that he needed someone The king knew that he needed someone clever like Archimedes to help him. clever like Archimedes to help him.

Archimedes wanted to help King Tubby. He Archimedes wanted to help King Tubby. He felt that the King should have a real gold felt that the King should have a real gold crown since the King spreads peace across crown since the King spreads peace across the lands! the lands!

• AND, if the goldsmith was a thief, a cheat, AND, if the goldsmith was a thief, a cheat, the King will lock him up in jail to the King will lock him up in jail to reeducate him!reeducate him!

But how could Archimedes find out if But how could Archimedes find out if the crown was real without ruining the the crown was real without ruining the crown? crown?

?????

• That night, Archimedes wanted to take a That night, Archimedes wanted to take a bath. While filling the tub, Archimedes was bath. While filling the tub, Archimedes was so busy thinking about the crown that he so busy thinking about the crown that he filled the tub with too much water. filled the tub with too much water.

Archimedes got into the tub and water Archimedes got into the tub and water spilled all over the floor!spilled all over the floor!

Archimedes wondered why the water spilled out Archimedes wondered why the water spilled out when he got into the tub. when he got into the tub.

He realized that there wasn't enough room in the He realized that there wasn't enough room in the tub for him and all that water! tub for him and all that water!

So how much water will spill out if he So how much water will spill out if he puts something in the tub? Archimedes puts something in the tub? Archimedes took his bath toys and did some took his bath toys and did some experiments.experiments.

The bigger something was, the more The bigger something was, the more water spilled. So even if a bath toy had water spilled. So even if a bath toy had a unusual shape, he could tell how big a unusual shape, he could tell how big it was by how much water spilled out. it was by how much water spilled out.

7

Archimedes noticed that some things that Archimedes noticed that some things that were were bigbig were very light and floated. But were very light and floated. But some things that were some things that were smallsmall were very were very heavy and sank. heavy and sank.

• Archimedes called how heavy something is Archimedes called how heavy something is (mass) compared to how big it is (volume) (mass) compared to how big it is (volume) the density. Different the density. Different materialsmaterials all have all have different different densitiesdensities..

Story BreakTech Demo: Determining Density

Sporadic.disillusionment@gmail.com - kippdynasty - nationtime. Density at 0 4.7 and 10

Little things like rocks had more density Little things like rocks had more density and sank. But his big toy alligator had less and sank. But his big toy alligator had less density and floated.density and floated.

Archimedes could put the crown into the Archimedes could put the crown into the tub to find the density of the crown, telling tub to find the density of the crown, telling him if the crown was made of gold or him if the crown was made of gold or something else.something else.

Now Archimedes knew how to find out if Now Archimedes knew how to find out if the crown was real gold. He was so excited the crown was real gold. He was so excited he shouted "Eureka!", which is Greek for "I he shouted "Eureka!", which is Greek for "I found it!"found it!"

He got up and went running through He got up and went running through the streets in a white towel shouting the streets in a white towel shouting "Eureka! Eureka! Eureka!""Eureka! Eureka! Eureka!"

Archimedes was so excited that when he got Archimedes was so excited that when he got out of the bath he forgot to put on his clothes, out of the bath he forgot to put on his clothes, keeping it real with his indigenous style! keeping it real with his indigenous style!

Archimedes ran to King Tubby and announced Archimedes ran to King Tubby and announced that he could figure out if the crown was really that he could figure out if the crown was really made of gold. King Tubby said "That's great, but made of gold. King Tubby said "That's great, but first put on some clothes!" first put on some clothes!"

• We now call his discovery We now call his discovery The Archimedes The Archimedes PrinciplePrinciple, which states that an object placed , which states that an object placed in a fluid has a buoyant force upward equal in a fluid has a buoyant force upward equal in weight to the fluid displaced (pushed out in weight to the fluid displaced (pushed out of the way) by the object. of the way) by the object.

Ticket to Leave1.1. When you fart underwater what gets released?When you fart underwater what gets released?

2.2. Are the gas bubbles more dense or less dense than water?Are the gas bubbles more dense or less dense than water?

3.3. Draw a picture and diagram of the forces at work. Draw a picture and diagram of the forces at work.