Motor principle-motor lab

The motor lab based on faraday's motor principle was conducted last class. It was a good experience overall. The best part about it was the me and my partner were proud of ourselves for being the firsts ones finished and getting the motor to work in one try. The reason it worked for us was because our brushes were installed correctly and the main part which was the coiling of the copper wire was done correctly(i.e the direction of the coil was one way only). Some groups motors did not work because either their wire was not wrapped around the cork properly or the brushes were not sanded properly and/or they were not placed in the correct position and therefore were not touching the commutator pins.

Notes from pages 553-563

• Sources of electrical energy: Voltaic cells - e.g; common dry cells batteries for portable electric devices. Piezo electricity - e.g; phonograph cartridges, barbecue spark starters. Thermoelectricity - e.g; gas appliance pilot light safety system; current keeps gas value open as long as flame is lit. Photo electricity - e.g; satellite and international space station supply, calculator power supply. Electromagnetic induction in generation - e.g; hydro, nuclear, fossil-fuel-powered electric generators.
• Amount if energy transferred depends on two things; the potential difference of the power supply and the nature of the pathway through the loads that are using the electric potential energy.
• The more difficult the path, the more oppostion there is to flow. The measure of this opposition to flow is called resistance. 
• Ohm's law: R = V/I  --> R (resistance in volts/ampere), V (difference in volts), I (resulting current in amperes)
• The resistance of a conductor depends on its length, cross-sectional area, the material it is made of and its temperature.
• The gauge number of a wire indicates its cross-sectional area. A wire that has a small gauge number has a large cross-sectional area. Similarly, a small cross-sectional has a large gauge number. 
• In a series circuit, the loads are connected one after another in a single path, whereas in a parallel circuit, they are side by side. 
• Kirchhoff's current law; the total amount of current into a junction point of a circuit equals the total current that flows out of that same junction.
• Kirchhoff's voltage law; the total of all electrical potential decreases in any complete circuit loop is equal to any potential increases in that circuit loop. 
• In any circuit, there is no net gain or lose of electric charge or energy.
• Superconductivity is the ability of a material to conduct electricity without heat loss due to electrical resistance. The promise of superconductors is transmission lines that carry electricity without energy loss.
• Three-way light bulbs, which have three different light intensity settings, have two filaments of different  resistance connected in parallel. Each filament can be turned on separately, or they can both be turned on at the same time, thus producing three different light intensities. 

Ohm's Law Pre lab

NAME-SYMBOL-UNIT-DEFINITION

Potential Difference -V- volts - the difference of electrical potential between two points
Current- I - A- a flow of electricity which results from the ordered directional movement of electrically charged particles

Resistance - R - Ω - a resistor or other circuit component that opposes the passage of an electric current
Watts- p - W - a unit corresponding to the power in an electric circuit in which the potential difference is one volt and the current one ampere

Highest Structure Challenge thoughts

- Worlds tallest buildings always have a very firm and stable base. Thats means that they have a more weight on the bottom than  the top of the structures or otherwise called as low center of gravity.
- In order to make tall structure stable, it must a wide base and good support. An example would be the CN tower; it widens towards the bottom as the four supports spread and that causes more weight. Even though the there is a large circular piece at the top, its still not as wide as its base.
- Another example would be the worlds tallest building, Burj Khalifa. It starts with what looks like a bunch of large coin stacks and as it gets taller some coin stacks stop and eventually one pile is what the highest point of the tower is. Some can even say that it looks like an ice cream cone upside down.

Pgs 544-552 points

- conductors carry charge like pipe carries water. The flow of charge is called elected current.
- the total amount of charge moving through a conductor divided by the time it takes to get past a point is how u calculate the current. It is calcated in amperes.
- a current measuring device is called an ammeter. 
- an ammeter measures the by taking energy fronthe negative wire and giving it to a load through a positive wire and finall returning back to he power source. That is also how a complete circuit works.
- an electric charge  has a certain amount of electrical potential energy.
- a voltmeter measures the difference of potential energy before and after it has been delivered to the load.
- a voltmeter is a heavy resistor so it can measure minimal current from the circuit.
- electrical energy always originates from other forms of energy.
- the conversion of other type of energy in to electrical potential energy can be done by many devices.
- instead of drawing diagrams for circuits, we use schematic drawings to easily understand where the current is going through.