electro magnetic

3 WAYS TO INCREASE THE STRENGTH OF AN ELECTROMAGNET
* INCREASE NUMBER OF COILS THAT WRAP AROUND THE CORE
* INCREASE THE CURRENT FLOWING THROUGH THE COIL
* CHANGE THE CORE MATERIAL TO BEST SUIT THE ELECTROMAGNET

http://spreadsheets.google.com/ccc?key=0AhmcrnKDxOH9dDhyOXBsdlYxTU1VYWNVN0ZxekQ3eXc&hl=en

what are magnetic flux lines??

magnetic flux is a measure of the magnetic field strength existing on a two dimensional surface, such as one side of a magnet

RULES FOR FLUX LINES.

1.cant cross
2.try to shorten
3.north to south
4.cant be broken

4 things i found hard in the exam

4 things i found hard in the exam..
well everything in the exam was harder then i thourt it would be and my mind was not set on the exam.

solving resistors

If R1 = 95Ω
R2 = 62Ω,
R3 = 7Ω,
R4 = 5Ω,
R5 = 22Ω,
R6 = 68Ω,
First you add up the right side resistors becuase they are in series. so R3+R4+R5=7+5+22=34ohms.
Then you would redraw the circuit with just one resistor instead of three with the resistance 34ohms.
Then you would work out the resistance of R2 and R3 by the parallel formula 1/R1 + 1/R2 = RT
so 1/62 + 1/34 =
Then you would add up all the resistances to get the total resistance.

spreed sheet

here is my spreed sheet

here is my spread sheet