Hi Guys,

So I am going through the electronics book, am on Vol 1 DC Chapter 5. I was reading the current calculations for a series circut and am a little confused as to how the author reached 500 MicroAmps when from what I know it should be 500milliAmps. Link to page.

So 9v/18k ohms = 0.5 AMPS. Moving the decimal 3 to the right gives us 500mA not 500microAmps as we moved the decimal -3 places (milli) and not -6 (micro).

Thats from the little I know. Can someone please clarify ..

EDIT: Ahh! Got it, 18k = 18000 ohms! I forgot about the zeros. Still getting used to the metric notation!

 

Got a calculator? Mine shows that 9/18,000 = .0005, or 500 microamps.

 

u got simple mathematical mistake its 9/18k=0.5m=500u

 

Thanks guys. I figured I was missing the zeros as soon as I submitted my post.
BTW, is there any shorthand for 'micro' other than the upside down h ?

 

Yes. u or µ

How to print µ?

Press <ALT> and hold it down, then press "0181", release <ALT>.

For Ω press <ALT> and hold it, then press "234", release <ALT>.

http://forum.allaboutcircuits.com/showthread.php?p=104455#post104455

Bill's Index

 

Cool, thanks bill. Alt+234 gives me Û

Another Q, is voltage drop the amount of voltage used/lost on a given load ?

 

Basic Ohm's Law, useful forever.

V=I/R
I=V/R
R=VI

Did you see the omega symbol on my posts?

 

I did see the omega symbol.

Im not with you with regards to the Ohms bit though.

Also, whilst I am gaining all of this theoritical knowledge I want to apply it so that I gain some practical experience and it sticks. Do you have any 'coursework' I can do per chapter (not more theory stuff but practical) ? And can you recommend any 'starter' kits that have all that I need ?

 

Hello,

At the top of the page you have the blue tabs.
These are entries to the eBook series.
For paractical experiments you can have a look at Vol VI - EXPERIMEMENTS:
http://www.allaboutcircuits.com/vol_6/index.html
For the worksheets (with hidden answers) you can have a look under the WOEKSHEETS tab:
http://www.allaboutcircuits.com/worksheets/index.html

Bertus

 

Thanks Bertus.
There are quite alot of tools I will need ! Are there any starter kits which contain most if not all of the tools I need ?

 

Hello,

Where are you located?
If we know that we can give you a better advice on where to buy your parts needed.

You can also take a look at this thread: Starter Kit

Bertus

 

Hello Bertus,

I am fron britain.

I was looking at a few electronics toolkits and here is what I found:

http://cpc.farnell.com/jsp/displayProduct.jsp?sku=TL12005&CMP=e-2072-00001000

http://cpc.farnell.com/duratool/d00029/electronics-tool-kit/dp/TL10269?Ntt=electronics+toolkit

They dont include an resistors, caps etc but they have all the 'tools' I need to get the job done.

Which kit do you guys think would be most idea for me as a beginner ?

 

Hello,

The cheaper one (duratool) looks sufficient.

You also might take a look at this experiments box:
http://www.maplin.co.uk/amazing-144-educational-experiments-science-station-228276

Bertus

 

Basic Ohm's Law, useful forever.

V=I/R Really? I thought V=IR
I=V/R
R=VI I thought it was R=V/I

Did you see the omega symbol on my posts?

Sometimes my fingers have a mind of their own, too.