2. BENJAMIN FRANKLIN
• Benjamin Franklin lived from 17 January
1706 to 17 April 1790.
• Benjamin was the 6th president of
Pennsylvania and was one of the
Founding Fathers of United States.
• Franklin had many professions, he was a
leading author, printer, political
theorist, politician, postmaster, scientis
t, musician, inventor, satirist, civic
activist, statesman and diplomat.
3. BENJAMIN FRANKLIN
• Benjamin’s electricity discoveries and theories have
contributed a lot to the history of physics.
• Franklin invented the lightning rod, bifocals, the Franklin
stove, a carriage odometer, and the glass armonica.
4. THEORY ON ELECTRICITY
• Electricity is a form of energy that results from the flow of charged
particles.
• Benjamin Franklin was the first to label electricity under different
pressures as positive and negative respectively.
• Franklin was also the first one who discovered the principle
of conservation of charge.
5. BENJAMIN CONDUCTED HIS FAMOUS KITE EXPERIMENT
TO PROVE THAT LIGHTNING WAS STATIC ELECTRICITY.
6. HIS FAMOUS KITE EXPERIMENT
• Benjamin tied an iron key to the end of a silk string and inserted a thin metal wire
that was tied to the key to a Leyden jar.
• When the thunder storm cloud passed over Benjamin's kite, the negative
charges in the cloud in the form of lightning passed onto his kite and down into the
Leyden jar.
• Benjamin then confirmed that lighting was static electricity.
8. CONCEPT OF COOLING
• Benjamin observed that he stayed cooler in a wet shirt in a breeze
than a dry one.
9. STEP BY STEP EXPERIMENT THAT BENJAMIN CONDUCTED
• Ben continually wet the ball of a mercury thermometer with
highly volatile liquids such as solvents.
• With each subsequent evaporation, heat is lost and the
temperature decreased to -14 degrees eventually while the room
temperature is still 18 degrees.
• Franklin was able to decrease the temperature of objects and
reduce its heat via evaporation of highly volatile liquids below
their freezing points.
10. WAVE THEORY OF LIGHT
• Ben was the only major scientist who supported Christiaan
Huygens' wave theory of light.
• It was basically ignored by the rest of the scientific community.
• The theory was proved to be true; but only after Young's famous slit
experiment where the scientific community was convinced.
