What Does High Resistance Mean What Does High Resistance Mean in Art

sgstudent

They say that nichrome is a ameliorate heating element as it has a higher resistance. Only if I take V=RI then own't I decrease since R is high, so current is lesser. Thus, resulting in a lower power dissipated as rut?
Also, they aq if I use the wrong wires like sparse wires, information technology will crusade a lot of heat produced as thin wires has a lot of resistance. Using the same reasoning I don't get why college resistance results in greater power...

If electric current is constant then greater resistance results in greater ability only I thought that voltage is usually abiding? So when R increases, I will subtract and cause low power?

Thanks for the help!

russ_watters

Who are "they"? They're incorrect.

AlchemistK

Who are "they"? They're incorrect.

Nichrome is a good heating chemical element.

From Wikipedia :
"A heating element converts electricity into rut through the process of Joule heating. Electric electric current through the element encounters resistance, resulting in heating of the element.
Most heating elements use Nichrome lxxx/20 (80% nickel, 20% chromium) wire, ribbon, or strip. Nichrome lxxx/20 is an ideal material, because information technology has relatively high resistance and forms an adherent layer of chromium oxide when information technology is heated for the starting time time."

willem2

If y'all want to blueprint a washing machine, or a water cooker, you know in advance what power the heating element should produce, and then you know the resistance information technology should have.

You can so apply a short thick wire fabricated of nichrome, or a longer or thinner wire made of another material with a lower resistivity.
If y'all make the wire thinner, it will also become hotter, because the same amount of heat has to period through the smaller expanse of the wire.
If you make the wire longer, it won't fit.

So yous accept to brand the wire both thinner and longer, and it will take to be rolled up somehow inside the heating element, if you don't want to make the heating chemical element itself larger.
Electrical isolation will be a pain, since plastic, safety etc. won't stand the heat, and you lot probably need a ceramic around the wires.

cjameshuff

You lot're forgetting the resistance of the power source and transmission lines. If the heating curlicue were made of a similar length of like gauge copper, it would draw huge amounts of electric current, but nigh of the voltage would be dropped beyond wiring rather than the heating element.

OJFord

They say that nichrome is a ameliorate heating element as it has a higher resistance. Only if I take V=RI then ain't I decrease since R is high, so current is lesser. Thus, resulting in a lower power prodigal every bit rut?
Also, they aq if I apply the incorrect wires similar thin wires, information technology will cause a lot of heat produced equally thin wires has a lot of resistance. Using the same reasoning I don't become why higher resistance results in greater power...
If current is constant so greater resistance results in greater ability but I thought that voltage is usually abiding? And so when R increases, I will decrease and cause low power?

Cheers for the help!

[itex]P = I^{2}R[/itex]

So every bit resistance increases, power does also...

willem2

[itex]P = I^{2}R[/itex]
So equally resistance increases, power does likewise...

This is not the equation you use, when y'all design an apparatus with a heating element in it.
Y'all know that the voltage across the resistance volition be equal to the mains voltage, and that the the power must be whatever is needed to bulldoze your pilus dryer, toaster or any.

The resistance is thus fixed by P = V^2/R, and the just question is what material, length and width to utilise to make such a resistance. Run into my before post.

OJFord

This is non the equation you utilise, when you design an appliance with a heating element in it.
You know that the voltage beyond the resistance will exist equal to the mains voltage, and that the the power must be whatever is needed to drive your hair dryer, toaster or whatever.
The resistance is thus fixed by P = 5^2/R, and the just question is what material, length and width to use to make such a resistance. See my earlier post.

Apologies, I didn't really read the question fully.

Just regardless, if y'all do not assume that you lot are working in this manner, the equation P=I^2R holds true for heating elements, surely?!

Ie, I'm testing some different elements of varying resistance, and recording the power output when driven from the aforementioned source. P will be greater for elements of greater resistance - that'southward all I was maxim.

Born2bwire

Apologies, I didn't really read the question fully.
Merely regardless, if you lot do not assume that y'all are working in this fashion, the equation P=I^2R holds truthful for heating elements, surely?!

Ie, I'm testing some dissimilar elements of varying resistance, and recording the power output when driven from the same source. P will be greater for elements of greater resistance - that'due south all I was maxim.

Both equations are valid when talking most power, but the bespeak here is that we are connecting our heating chemical element to a voltage source. And so the the voltage beyond the circuit is going to remain the aforementioned as long equally the current describe is within reason. That's why yous work from Five^ii/R. At present if you use I^2R, the problem is that the current is going to change due to the equivalent resistance of your circuit. Then while you may increment the resistance, you will also meet a decrease in the current from the same voltage source.