# typo?

Discussion in 'Feedback and Suggestions' started by skfir, Aug 18, 2010.

1. ### skfir Thread Starter Guest

In the chapter "resonance"
/vol_2/chpt_6/6.html
when it is about parallel resonance circuit, the parallel circuit is, in my opinion, mistakenly called to be a series.

"A parallel resonant circuit is resistive at the resonant frequency. (Figure below) At resonance XL=XC, the reactive components cancel. The impedance is maximum at resonance. (Figure below) Below the resonant frequency, the SERIES resonant circuit looks inductive since the impedance of the inductor is lower, drawing the larger proportion of current. Above resonance, the capacitive rectance decreases, drawing the larger current, thus, taking on a capacitive characteristic."

2. ### skfir Thread Starter Guest

There are also some little typos: "prodces a low peak"

3. ### Wendy Moderator

Mar 24, 2008
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Why not register, you can interact in more detail, and it is free?

Thanks for the feedback.

4. ### Skfir Senior Member

Aug 19, 2010
137
4
Yes, you are right, sorry. Thanks.

Apr 5, 2008
19,264
3,887
Hello,

Welcome to the forum.
Good to hear you like the site.
If you have any questions, start asking.
We will be happy to answer the questions.

There is also the eBook, see the tabs on the top of the page.
Did you also look at the useful websites thread:
Useful websites for electronics (Ver. 2)

Bertus

6. ### Skfir Senior Member

Aug 19, 2010
137
4
Thanks mate! I did. It seems I found some typo again:

/vol_2/chpt_8/6.html

"The output voltage to the load at this point actually exceeds the input (source) voltage! A little more reflection reveals that if L1 and C2 are at resonance, they will impose a very heavy (very low impedance) load on the AC source, which might not be good either."

There is no C2 there

7. ### Wendy Moderator

Mar 24, 2008
21,524
2,972
18 paragraphs down, about 2/3 down the chapter.

Unexpected response of L-C low-pass filter.

What was supposed to be a low-pass filter turns out to be a band-pass filter with a peak somewhere around 526 Hz! The capacitance and inductance in this filter circuit are attaining resonance at that point, creating a large voltage drop around C1, which is seen at the load, regardless of L2's attenuating influence. The output voltage to the load at this point actually exceeds the input (source) voltage! A little more reflection reveals that if L1 and C2 are at resonance, they will impose a very heavy (very low impedance) load on the AC source, which might not be good either. We'll run the same analysis again, only this time plotting C1's voltage, vm(2) in Figure below, and the source current, I(v1), along with load voltage, vm(3):

8. ### Skfir Senior Member

Aug 19, 2010
137
4
Yes, I inderstand, but sorry, there are c1, l1, l2, rload on the schematic, but not C2, I am just a bit confused...

9. ### Wendy Moderator

Mar 24, 2008
21,524
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I don't think anyone is arguing, I was pointing out the specific location for our editor, Dennis Crunkilton. Finding this stuff can be challenging.

10. ### Dcrunkilton E-book Co-ordinator

Jul 31, 2004
418
11
Thanks Skfir for pointing out these two typos. I have made the corrections in the master copy at ibiblio.

Dennis Crunkilton

11. ### Skfir Senior Member

Aug 19, 2010
137
4
No worries mate! A bit more:

/vol_2/chpt_13/2.html

A motor driven by square waves of current, as proviCed by simple hall effect sensors,

May it must be written "provided"?

12. ### Skfir Senior Member

Aug 19, 2010
137
4
Here
/vol_2/chpt_13/6.html

It is also possible the put the rotor on the outside surrounding the stator.

Should it be TO put the rotor? Sorry, I am far from being an native English speaker, so, I don't know...

13. ### Skfir Senior Member

Aug 19, 2010
137
4
One more thing about the chapter "AC motors" Wouldn't it be better to start the chapter from "Tesla motors"? Because all the basics of AC motors, torque and motion itself are explained in that very part. When I red "Synchronous motors" which is the first one currently, I had many things I didn't really understand, until I red "Tesla motors" part...

14. ### beenthere Retired Moderator

Apr 20, 2004
15,808
294
Yes, that is correct.

That is more technically correct, but not everybody recognizes Tesla's contribution to the development of the AC motor. You might notice that credit is given to Tesla in the material.

15. ### Skfir Senior Member

Aug 19, 2010
137
4
/vol_2/chpt_13/12.html

He formlated the laws of magnetic hysteresis in finding a solution.

Should it be said formulated?

16. ### beenthere Retired Moderator

Apr 20, 2004
15,808
294
"Formulated" is correct.

17. ### Skfir Senior Member

Aug 19, 2010
137
4
/worksheets/static.html

question 5
This mechanical work becomes ßtored" in the electric field

Is it to be said "Stored"?

18. ### beenthere Retired Moderator

Apr 20, 2004
15,808
294
Also correct.

19. ### Skfir Senior Member

Aug 19, 2010
137
4
/vol_1/chpt_12/9.html

Tables of specific resistance and temperature coefficient of resistance for elemental materials (not alloys) were derived from figures found in the 78th edition of the CRC Handbook of Chemistry and Physics.

Table of superconductor critical temperatures derived from figures found in the 21st volume of Collier's Encyclopedia, 1968.

Good! But there is nothing there

20. ### Wendy Moderator

Mar 24, 2008
21,524
2,972
Suggestion, use full links, like this...