(A KLOPP) Homework 9/14

1. Brainstorm realistic and unrealistic ideas for midterm project. Observe interactions between people and people, people and the environment, and people and machines. Record these observations.
Realistic: led illuminated design like some of the artists I mentioned in the previous 3 artists blog post, interactive kinect project, interactive LED design piece of wall art
Unrealistic: machine like the one from my META class will take too much time 
Observations:  People expect instantaneous results from machines, machines expect proper input from people; people expect little from the environment (nature can rain when it wants to rain), nature expects little from people (nature makes due with what it is given); people expect something in between from one another. 

2. I already turned in my labeled circuit board on the blog earlier. 

3. Read p. 36-80 in the Manga Guide to Electricity

4. Check out Brea Souder, Zane Berzina and Jackson Tan

5. Document yourself creating some static electricity and post to the blog. Use the triboelectric series to decide which materials to use to generate static electricity.
Static electricity that is generated by friction in this way (rubbing hair on vinyl sheet) is also called frictional electricity or triboelectricity. 

Triboelectric series includes (in descending order):  human skin(+), glass(+), human hair(+), nylon(+), wool(+), silk(+), paper, cotton, steel, wood, rubber(-), copper(-), polyester(-), polythylene(-), and vinyl(-). *these (+/- vary depending on the relationship in the series).

Air purifier- uses static electricity to attract fine dust(-) to the filter(+) according to Coulumb's force.

6. Contrast the speed of an electron with the speed of electrical motion in one sentence.
Electrons move in the opposite direction of current, electrical motion moving quickly while electrons move slowly.

7. Briefly explain the relationship between resistance and energy. Use an example from your house.
Resistance is represented by Ohms. Resistance is what makes an LED illuminate. For example, when I turn on my TV, the lights from the TV convert electrical energy from the electrical outlet, flowing to light energy on the TV. 

8. What is the difference in AC and DC current. Give an example of each in daily life.
Direct current and Alternating Current circuits are different because one has a fixed size of current and the other does not. When the electricity is fixed, it is a directed current (DC).  For example, a battery (9V for example) is a fixed current and therefore DC. An example of AC current in daily life is my computer charger using the outlet from the library to charge my computer. The size of this current varies cyclically with time. There is a peak voltage and an instantaneous voltage to AC power supplies. Peak voltage for power supplies in an electric outlet is about 170V versus what most United States homes carry in electric outlets:  about 120V. 

9. Determine the equivalent resistance of a 6.0 Ohm and 8.0 Ohm resistor if connected in a series versus connected in parallel.
The method of connecting resistances in a line is called a series connection. We calculate the value of the effective resistance in a series connection by totaling the individual resistance values. If two light bulbs are connected in series to a power supply, the current will be 1/2 of what it would be with only one light bulb. However, in a parallel connection, you calculate the reciprocal of the sum of the reciprocals of each resistance. If two light bulbs are connected in a parallel circuit they will be equally bright as if there were only one light bulb in the circuit. 

Series
6 + 8 = 14 equivalent resistance

Parallel
1/(equivalent resistance) = 1/6 + 1/8 = 3.4 equivalent resistance