Atomic Energy

• Cash money

• Increased trade & shipping

• The compass

• Meteorology

• Cloud chamber

• Splitting the atom

700 BC – “Touchstone”

• A schist mineral in Lydia (Turkey)

• Standardized precious metals and alloys.

• Gave credibility to the king’s mint.

• Provided a unifying effect on the state and permitted selective buying.

• Increased trade.

Lydian Coinage 500 BC

331 BC –Alexandria

• Strategically Located at the mouth of the Nile.

• Developed into the largest international seaport.

• The library had copyrights for all incoming manuscripts.

Ancient Alexandria

From Cleopatra VII exhibit @ Science Center

90-168 AD – Claudius Ptolemy

• Alexandrian Professor

• Wrote ‘Mathematike Syntaxis’ a composition of all known astronomy and star locations.

• An Idea far ahead of its time.

• Important navigational tool in 15th Century.

8-13th Century Ship Improvements

• Incorporation of lateen (triangular) sail

• The stern post rudder

• The compass

• Increased trade

• Ships became fatter, squarer, longer and fuller.

“South-pointer” 2200 BP

• First used in China for divination or feng shui.

• The pointer evolved into the compass for navigational purposes in 11th century China.– Western Europe 12th

century.Modern compass

Fall of Constantinople

• Seized by Turks in 1452

• Ended easy passage to the East

• Navigation around Africa & West was made easier with the compass – but it erred!

Portugues & Spanish Conquistadors

• Chrisopher Columbus 1492

• De Gama - 1497-98 first to “round the hope.”

• Amerigo Vespuchi - 1501 found Americas.

• Magellan - 1519-22 circumnavigated globe

• Sir Francis Drake brought back much gold (4000% profit) which may not have made it back do to compass error in 1581.

Dr. William Gilbert

• Spent 18 years solving the riddle of the errant compass needle.

• Told us the compass always points to the magnetic north pole of the earth.

• In 1600 he published De Magnete. Falsely credited magnetism as gravitational force. However suggested that a vacuum existed between the planets.

True & Magnetic North

• Presently Magnetic North is moving NNW at 25mi/yr.

Learn more about magnetic North migration

1646 – Otto von Guericke invented the vacuum pump. • Introduced us to

the vacuum & electricity.

• He published his work in 1672.

1750 – Ben Franklin

• Invented the theory of positive and negative charge attraction.

• Invented the metal lightning rod.

1800 – Hot air balloons

• Done for fun and to collect meteorological data.

1854 – Hurricane disaster of French ship, Henri IV.

• This triggered the increased number of weather observatory stations.

1883 – Ben Nevis weather station in Scotland

• Charles Wilson observed a glory here, which led him to invent the cloud chamber to study cloud formation.

• Discovered radiation or charged particles (ions) form clouds. Glory

Wilson Chamber

• The streaks are caused by He+2 and e- particles emitted from radioactive decay.

• Thick streaks from He+2 ions.

Radar

• Cambridge professors Wilson and Appleton, who discovered radio waves bounced off the “Appleton Layer” contacted Watson Watt.

• In 1935 Watson Watt invented RADAR.

1912 - Ernest Rutherford

• Used Wilson’s cloud chamber to study atoms under bombardment.

• This tool led to the discovery of nuclear fission and the atomic bomb.

Nuclear Fission

• The splitting of fissionable material such 235U or Pu into smaller elements, energy and three free neutrons.

• Some matter is changed into energy

• Fusion is the opposite of fission.

Summary

Electricity

• Voltage = Current x Resistance

• Power = Voltage x Current

Direct and Inverse Variables

Y= 4x

Y= 4/x

As x increases y increases by same proportion

Direct

Inverse

Some mathematical expressions.

• E= mc2

• PV= nRT

• E= h

• E= hc/

• E=mv2/2

• Voltage = Current x Resistance

What you should know

• Describe early gold purification methods, in Burke pg. 15.

• How did the touchstone affect trade? Slide #2

• How did cash money affect trade. #2

• How long was it before Ptolemy’s star charts were used for navigation?

• How did the lateen sail affect trade and navigation?

• Burke pg. 15 (golden fleece)

• Increased (see slide #2)

• Increased (see slide #2)

• 1400 years later after ship improvements & Turks conquered Constantinople (slide #9)

• Increased by allowing “tacking” into the wind. #7

What you should know

• Describe the accomplishments of Otto von Guericke on magnetism, vacuum and electricity, 32-34.

• How was radio detection and ranging developed from weather forecasting, 39-42

• Describe the accomplishment of Gilbert on the compass, vacuum & magnetism, 30-31

• Read Burke 32-34

• RADAR read Burke 39-42

• Explained Earth’s magnetic field. True North vs. Magnetic North (see Burke 30-31

What you should know

• What is the relationship between energy, E, and wave length of light, , in the equation E=hc/ ? (Direct or inverse)

• If power is constant and voltage is decreased 10 times, how would current be affected?

• As wave length gets larger energy (E) gets smaller. They are inverse.

• Power = current x volts thus current must increase by 10x