1. Physics 12 Mr. Jean November 28 th, 2011

2. The plan: Video clip of the day Finish Tesla’s Lost Lightning video Results from Lab –Observations etc… –How speakers work, and motion caused by current. Element Charge particles Complex Circuits (Intro)

3. Tesla’s Lost Lightning Last 30 minutes or so of video

4. Solar Power Night & Day: In Spain they were able to achieve solar power creation in the middle of the night. This experimental facility was producing vast quantities of power in the dark of night.

5. Solar Power at Night: How could this be? Take the next 5 minutes and discuss with your neighbour how this could be.

6. How was this accomplished? The owner found that by using government subsidies for green energy they could make more money if… They would shine large diesel powered spotlights into solar panels all night.

7. How was this accomplished? This results in huge profits. For every dollar of fuel used they were able to produce 1.40 or so by selling their “solar power”. Before getting caught they increased their carbon footprint by over 2000%. Personal option: There is not enough room on this planet for greedy people.

8. Resistance for wire Nichrome wire –1meter –22 gauge –ρ = ?

9. If you were to design a toaster: What type of resistance would be better if you were to design a toaster? ρ = 1.0 x 10 5 ρ = 1.0 x 10 -5 Why?

10. Resistance for a speaker: What type of resistance would be better if you were to design a set of speakers? ρ = 1.0 x 10 5 ρ = 1.0 x 10 -5 Why?

11. Observations about the wire: Observations between 0 – 0.5Amps? Observations between 0.5 – 2Amps? Observations for beyond 2mps?

12. How speakers work: Inside a speaker, an electromagnet is placed in front of a permanent magnet. The permanent magnet is fixed firmly into position whereas the electromagnet is mobile. As pulses of electricity pass through the coil of the electromagnet, the direction of its magnetic field is rapidly changed. This means that it is in turn attracted to and repelled from the permanent magnet, vibrating back and forth.

14. The frequency of the vibrations governs the pitch of the sound produced, and their amplitude affects the volume – turn your stereo up high enough and you might even be able to see the diaphragm covering the cone move. To reproduce all the different frequencies of sound in a piece of music faithfully, top quality speakers typically use different sized cones dedicated to high, medium and low frequencies.

18. Elementary Charge: This represents the number of electrons which pass through a system. q = Ne q = Amount of charge in coulombs N = Number of electrons (NO UNITS!) e = charge of electron. (1.6 x 10 -19 C)

19. Example: A light bulb draws a current of 0.6A. The light is left on for 480s. 1) How many electrons passed through the bulb?