AC sinewave

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1. R.M.S what is it? : R.M.S stands for the route mean square, so we times the peak value X .707 to calculate the R.M.S.

2. what is the peak? : the peak is the positive of the sine wave whereas the trough is the negative of the aforementioned sine wave.

3. what does peak to peak mean? : if we are using a 50 Hz device its peak to peak would be 650 V because the peak and trough are both 325 V so we just add them together.

4. what is the frequency? : frequency is the amount of wave lengths (or revolutions) per second. so 50 Hz means  50 times per seconed.

5. what are wave lengths? : the length of a single wave is 360 degrees.

worldcup spread sheet

Here is my spreadsheet

4 rules of flux lines

1. they always radiat from north to south.

2. they never intersect.

3. they cant be broken.

4 they always try to shorten themselves.

what will the test tommorow contain?

i think these 8 topics will be covered.

1. vectors
2. resistor color code
3. E 12 & E6 range
4. multimeter comparison
5. conductors
6. temperature equations
7. networks
8.Si units

Resistor network

 If R1 = 97Ω,
R2 = 41Ω, R3 = 9Ω, R4 = 8Ω, R5 = 6Ω, R6 = 54Ω,

This is a Resistor Circuit, to find the total resistance you:

1. redraw circuit, add R3,R4 and R5 together so you have one resistor in parallel with R2.

2. calculate the combined resistance of R2 and R3 (made up of the old R3,R4 and R5) by placing them both under one and adding them.

3. find total current, V/R=I

4. use ohms law to find any other value required.

E12 resistor chart

here is my E12 resistor chart

Parallel Circuit

This is a parallel circuit, the current has 2 or more paths to follow so this allows the circuit to work even after the loss of one or more components. the equation for working out the values in slightly more complex than for the series circuit because the resistance values have to be added as fractions. the voltage is the same across all branches and the total current is the sum of the branch currents.

Series circuit

This is a Series circuit, the current has only one path to follow, if any of the components are removed then the current will cease to flow. the total resistance can be easily calculated by adding the individual component resistance. from there its simple ohms law for the rest of the values.

Resistor color code chart

we have recently been exploring the colored band on resistors, the chart above is an invaluable tool in being able to read and comprehend resistors.the resistor above the chart has a value of 22 ohms with a tolerance of 5%. 

Stress management presentation

Stress management

View more presentations from Our Group.

first week back and the topic is computer ergonomics.

Some factors that influence computer ergonomics are, back position, how high your monitor is set in relation to your eye level, what angle you set your keyboard at and even the angle of your knee (?????).

forth week at uni

last week we took some time out of our busy schedule to take a look at the various ways we can generate electricity and the pros and cons of each. we also did some small scale experiments (such as the one on the left) to help us understand the concept of power generation. one of the experiments we did was a small scale generator which is the primary way we generate electricity regardless of what we use to turn the magnet. the cylinder on the left is wrapped in copper wire, the ends of which are attached to two contacts. we can generate electricity by runing a magnet over the copper but to increase the generation rate we incerted a metal rod with a magnet on the end. when the rod and magnet were moved in and out we got a small charge across the contacts.








One example of electrical generation is nuclear power. while this is one of the most powerful and nearly limitless sources of electricity it is also one of the most dangerous.










the only example i need is the horrific accident at the power plant in Chernobyl, Ukraine.  

last week

well last week went well all things considering. the maths came easy due to the fact that i remember the simplicity of triangles.i would write more but the teacher wants to move on now.

Second week at uni

well another week has passed without any major problems and we have finally got stuck into the more practical side of things. soldering is probably my preferred activity out of the three activity's because its essential skill to have if we want to become spark's and it brings a measure of satisfaction and pride when the thing you are soldering looks like its supposed to when your done.

As for getting around uni i have located the coffee stall (essential in the mornings) and most of the food shops so i am well settled into uni life.

first week at Unitec

well im 16 and have just left school (Rangitoto college on the north shore) so this is a completely new experience to me but so far it is going well the class and lectures are good and the campus is better than i thought. the work so far has just been recapping on stuff we learned before so i haven't had a good taste of proper uni work but i think i can do it (famous last words probably).