# What is the name of the device used to measure ohms?

What is the name of the device used to measure ohms?

dextercioby
Homework Helper
With a multimeter,you can measure both tension & current,ergo determine resistence...

Daniel.

EDIT:I suspect a tool only for resistence would be called OHMMETER...

I need to be sure that it's called an ohmmeter though. I don't want to introduce to many calculations into my experiment, as it's only supposed to focus on how a wire's length, shape, mass, thickness, and material affect its resistance.

dextercioby
Homework Helper
It's not too many calculations,just a division V/I.In case you lack the ohmmeter.

$$R=\rho\frac{l}{S}$$

Is this what you're looking for...?

Daniel.

dextercioby
Homework Helper
Oh,and one more thing:I'm pretty sure that the ohmmeter used Ohm's law (!) to determine the resistance and doing that by performing the division,insted of you...

Daniel.

Ahhh...I found an ohmmeter, and yes, it does use Ohm's Law.

Also, do you know how a wire's mass would affect its resistance? I'd assume more massive wires would be less resistant...

dextercioby
Homework Helper
No,not directly.The ratio is (length/area) (times resistivity,see above).So mass is involved indirectly.

Daniel.

Okay. Also, why do electrons move faster and more effeciently through metals than nonmetals? What are the characteristics of a good conductor? Does it have something to do with the way the atoms or molecules of a substance are arranged?

dextercioby
Homework Helper
Of course.Internal structure is the key...Quantum Mechanics and Transport Phenomena give all the answers/explanations.

Daniel.

One more thing before I go, does the ohmmeter require electricity to be running through a wire to take its measurements, or does it test the material directly?

Integral
Staff Emeritus