{{:electricity:electricity-banner-790x50.jpg|Electricity Banner}} ====== Q6.1 If electrons move slowly, why does a light turn on instantly: ====== === CORE CONCEPTS: === If electrons move slowly, why does a light turn on almost instantly when I press a switch that is a long way away: ++++ Q6.1 CLICK HERE TO SEE / HIDE STUDENT FLIP RESOURCES:| {{youtube>jbi7gJTPSXk?640x360|How Fast is an Electron & Electricity}} **Video: How Fast Does An Electron (CURRENT) Travel** * IF UNABLE TO ACCESS YOUTUBE VIDEO (requires Flash) TRY:[[http://viewpure.com/jbi7gJTPSXk|How Fast is an Electron & Electricity]] {{youtube>-65a88MoQAA?640x360|How Electric Energy vs Electric Current Travel}} **Video: How Fast Does Electric ENERGY vs Electric CURRENT Travel** * IF UNABLE TO ACCESS YOUTUBE VIDEO (requires Flash) TRY:[[http://viewpure.com/-65a88MoQAA|How Electric Energy vs Electric Current Travel ---- ++++ ++++ Q6.1 CLICK HERE FOR A SCIENTIFIC EXPLANATION:| 'Electricity' doesn't flow inside metal wires - 'charges' do: Imagine a circle of railroad track and lots of freight cars/marbles back-to-back all the way around the tracks as the 'electrons' (With no engine of course) - Include enough freight cars/marbles so that you cover the entire circle of track. Then push one freight car/marble along, and you transmit 'kinetic energy' (movement) almost instantly to all the cars/marbles in the loop. The cars or marble represent the copper's electrons which flow within a wire. Electrons arrange themselves like a chain - The chain is made up of lots of individual bits that are tied together: If you tug one end, the opposite end will move almost immediately. The 'electricity' behaves like a chain, or more accurately, like the loop of a mechanical drive-belt: Even though the electricity flows quite slowly, wires can deliver energy almost instantly. (After all, if a drive belt should all move at once, then the main local drive-pulley can almost instantly move all the distant driven pullies all the way around the belt.) Many years ago, before motors and generators were invented, 'power companies' used leather drive belts and rotating drive shafts to send energy to their customers. This really happened! In those days most customers were located in a small area, and the 'power company' was just a huge steam engine in the middle of a factory. Energy was sent to all of the factory machines using long leather belts and metal drive shafts. Today power companies still use steam engines, although they're powered by nuclear reactors as well as coal or oil. If you think it through, electric wires and electric motors aren't so 'modern' or 'sophisticated' - they are really just a modern way to hide the leather belts that connect all the machines to the distant steam engine! ---- ++++