Download L1 in class - The College of Engineering at the University of Utah

EM Basics
• Dr. Cynthia Furse
• University of Utah
• Department of Electrical and Computer Engineering
• www.ece.utah.edu/~cfurse
1
Notes
• Were you able to get on the YouTube videos?
• New Lab Section added Tuesday 730-1030.
• Writing Lab starts Monday. Prelab – Read
article. See Lab website (linked to class
website). If you have a laptop with Word or
similar, please bring it. OK to go to any lab
section (even if not signed up), turn in work to
you assigned TA.
• Office hours today will be abbreviated (end at
1045). Email me if you need help.
2
Portfolio Question
*What are electric and magnetic
fields
* and what causes them? (What
are the sources?)
* What are their units, and the
units on all related constants?
3
Coulomb’s Law


F12  R12
q1 q 2
4o R12
2
ɛo electrical permittivity of free space =
8.854 x 10-12 F/m
F arad = Amp-Sec/ Volt
Newton = Joule/meter
Joule = Watt-Sec
4
Electric Field
 
ER
q
4o R
2
ɛo electrical permittivity of free space =
8.854 x 10-12 F/m
Electric Field (V/m)
5
Electric Flux Density
D=ɛE
2
(C/m )
6
Magnetic Flux Density


I
o
ˆ
B 
2R
μ = magnetic permeability (H/m)
μ o = 4π x 10-7 Henry/meter (permeability of free
space)
B (Tesla) = Weber / m^@
Weber = V-s
Henry = V-s/A
7
Magnetic Field
B = μ H Tesla
8
What do I turn in for today?
• Answer to Portfolio Question
• Derivation of units for F, E, B, H
• Turn this in on MONDAY at 5pm to the HW
locker by the ECE office.
• What else do I turn in on Monday ?
– HW #1 from Monday
– Portfolio 2 & HW #2 from today
– Portfolio 3 & HW #3 that will be assigned Friday
9