Discussion in 'Homework Help' started by A212, May 6, 2008.

1. ### A212 Thread Starter New Member

Apr 18, 2008
7
0
I need answer to thses qustions.​

1- Could you please explain the notion of electrical length.​

2- If I give you a physical length of an element and the operating frequency, how to be able to calculate the elements electrical length.

Thansk

2. ### Wendy Moderator

Mar 24, 2008
20,782
2,581
It's hard to tell from your questions, but it sounds like you're talking resonant lengths of wire for antennas. You're going to have to be a bit clearer phrasing your question.

This sounds like a school assignment too, which probably means it needs to be in the homework forum.

3. ### hgmjr Moderator

Jan 28, 2005
9,030
214
I agree with Bill. This does appear to be a homework assignment and so I have moved this thread to the homework forum.

Let me know a212 if we have misjudged you post as homework.

hgmjr (moderator)

4. ### Papabravo Expert

Feb 24, 2006
10,401
1,866
Electrical length is related to the wavelength of a signal propagating in a trasnmission line. It is also related to the properties of the materials and the geometry of the construction. Since wavelength times frequency is a constant we can see that electrical length changes as the frequency of the signal changes.

5. ### Dave Retired Moderator

Nov 17, 2003
6,960
147
You can calculate the electrical length in the said applications by:

$L_{electrical}$ = $3.1e-4\frac{L_{physical}*f}{V_{P}}$ (in metres)

$V_{P}$ is the velcoity factor is the wave velocity divided by the speed of light in a vacuum (obviously a value less than 1).

Dave