How To Get Resistance

Hi Olan.,

Maybe you could use a MULTIMETER it has voltage, current and resistance reading.
I have here a DIY multimeter circuit http://www.allaboutcircuits.com/vol_6/chpt_3/11.html

Hope it helps.

Now this is clever. Is it just my browser, or does everyone else see this ?
The question was asked 1 minute ago, and the reply is dated two days ago !
Has EEWeb invented a time machine ?

No attached diagram. Typically this is because it was not in one of the three forms:
* GIF
* JPEG [.jpg]
* PNG

Try converting it to one of these and post it again.

PDF might work, too, but not sure.

Yup, I see that, too -- weird.

Thanks for your reply, i have attached image to make my question clearer to you. Your contributions are welcome. Thanks

I re - edited my question that why it appeared like that.

Thanks, i have attached JPEG. Your contributions are welcome, thanks

The correct drawing for a voltmeter is a V in a circle.. In your diagram they appear as short circuits around the resistors.

Your equation is wrong. It should read R3 = V3/I

However, no current will flow in the circuit as drawn, because there is no voltage source.

Hello.

Please I need help on a circuit/component(s) that can calculate Resistance R4 from this circuit diagram attached. Thanks

Thanks, correction has been made in d voltmeter diagram. But my equation is right, that why i said i need another circuit/component that can calculate Resistance R4=V3/I

I'm not sure what you're asking. There is no R4 in your diagram, but if R4 = V3/I then R4 = R3.

Thanks for your reply, I want us to forget about R4. I think what I need is like a METER to give me ratio of V3/I.

I took a closer look at your diagram and it makes no sense if V1, V2 & V3 are voltmeters and A is an ammeter -- unless V1 = V2 = V3 = I = 0. Because there is no power source.

But, if you are looking for a meter to give you V3/I, then it sounds like you need an Ohmmeter, like some of the others have said.

In other words, V3/I = the resistance of whatever V3 is across. Now, if the component that V3 is across is not a linear positive resistance, or if it is, and at V3 it's being stressed in a way that would change it's resistance, then you will need two meters. One a voltmeter and the other an ammeter, and then some sort of dividing function -- since an ohmmeter will apply it's own voltage which will likely not be whatever V3 is.

So, maybe what you're looking for is the dividing function. There are several ways to do that, so let us know if that is what you want, and I/we will elaborate.

Dear Olan,
the ampere meter should be connected in series, maybe something hidden in your circuit and where is the source? If V1, V2 and V3 are volt meters you will only get the PD and not supply voltage.