0
How does the relation v equals ir apply to resistors that do not obey ohm law?
Wiki User
∙ 9y ago
Ohm's Law states that 'the current flowing through a wire at constant temperature is directly proportional to the potential difference across the ends of that wire'.
The ratio of voltage to current is the resistance of the circuit. For Ohm's Law to apply, this ratio must be constantover a range of voltage increments -in other words, Ohm's Law only applies to a circuit whose resistance is constant over a range of voltage increments. Resistors follow this rule.
However, the ratio of R= V/I applies whether Ohm's Law applies or not. For example, the resistance of a tungsten filament will increase as the voltage across it increases. So the ratio of voltage to current constantly changes for tungsten and, so, it does not obey Ohm's Law. However, you can still use the equation R = V/I to determine what the resistance happens to be for each voltage increment.
Wiki User
∙ 9y ago
Add your answer:
Earn +20 pts
Why does the relation v equals iR applicable to resistors they do not obey ohms law?
Ohm's LawVoltage = Current x ResistanceResistance is part of Ohm's Law. Not sure why you think there is some violation of Ohm's law as it applies to resistance.AnswerHardly any conductor or electrical component (e.g. diodes, etc.) obeys Ohm's Law. For Ohm's Law to apply, the ratio of voltage to current must remain constant for changes in voltages. In other words, if we were to plot current against voltage, for variations in voltage, then we should end up with a straight-line graph. But most conductors and devices produce curved-line graphs!The reason for this is that Ohm's Law is simply NOT a 'law' in the sense of being 'universal'.The equation, R = E/I, is actually NOT derived from Ohm's Law, but from the definition of the ohm.
What is the necessary condition for a conductor to obey ohm's law?
No. In fact, most conductors don't obey Ohm's Law.For Ohm's Law to apply, the ratio of voltage to current must remain constant for variations in voltage. For many conductors this simply doesn't happen and, for that reason, we call such conductors 'non-linear' or 'non-ohmic'.
What is the nature of the current voltage graph for an unknown resistor?
Fixed-value resistors are normally manufactured so that they obey Ohm's Law -that is, the ratio of their voltage to current remains constant for variations in voltage, within specified limits. In other words, their resistance value remains constant for variations in voltage. This would produce a straight-line curve when plotted. Devices and materials that do not obey Ohm's Law (e.g. semiconductors, etc.) would produce a curved line.
What happens to the current as the resistor approches infinty?
Most resistors are linear, or 'ohmic', devices -which means that they obey Ohm's Law. So the ratio of voltage to current remains constant for variations in voltage. In other words, their resistance remains constant -providing their power rating isn't exceeded. So you can say that, providing the current increase doesn't cause their power rating to be exceeded, their resistance should remain the same. Resistors wouldn't be of much use if their resistance value changed whenever the current through them changed!
Do pure semiconductor obey ohms law?
No semiconductor's do not obey ohm's laws.
Which type of star best obey mass-luminosity relation?
Main sequence stars
Why does the relation v equals iR applicable to resistors they do not obey ohms law?
Ohm's LawVoltage = Current x ResistanceResistance is part of Ohm's Law. Not sure why you think there is some violation of Ohm's law as it applies to resistance.AnswerHardly any conductor or electrical component (e.g. diodes, etc.) obeys Ohm's Law. For Ohm's Law to apply, the ratio of voltage to current must remain constant for changes in voltages. In other words, if we were to plot current against voltage, for variations in voltage, then we should end up with a straight-line graph. But most conductors and devices produce curved-line graphs!The reason for this is that Ohm's Law is simply NOT a 'law' in the sense of being 'universal'.The equation, R = E/I, is actually NOT derived from Ohm's Law, but from the definition of the ohm.
Do laws apply to cops?
Yes, even cops have to obey the law even though they have certain privileges that normal people don't have.
Is the verb obey to or just obey?
The verb is merely, obey. I obey, you obey, he, she, it obeys. One may be obedient to someone, but one does not "obey to" someone.
Does a spring which is not in its elastic region obey Hookes law?
No, by definition Hooke's law relates to linear elastic only; when outside the elastic region it does not apply.
How vacuum tubes do not obey ohms law in circuit design?
In point of fact, vacuum tubes do obey Ohm's law. Everything electrical obeys Ohm's law. The reason vacuum tubes don't appear to obey the law is that not every consideration takes into account the fact that vacuum tubs have dynamicresistance. Ohm's law, as applied to "pure" ohmic resistors, requires constant resistance, which no material, no matter how good, exhibits. In the real world, you have to consider that resistance can vary along with voltage and current, and this "complicates" things.
Sentence for the word obey?
Obey is a verb. Obey means "to do as told".Example:Soldiers should obey orders.
What is the present tense of obey?
Obey is present tense. I/We/You/They obey He/She/It obeys
What is the prefix of obey?
There is dis obey the prefix here is dis because it comes right before obey. You can use Re obey because you can obey someone another time for the same thing maybe. But everybody knows that you can use dis obey and maybe re obey Onother person: Prefixes can be dis-obey
In a series circuit each device that is added to the circuit decreases the what?
Depends on the device. If it is a resistor and you have a fixed voltage then the circuit will obey Ohms law. Voltage = Current x Resistance. So if R increases by adding more resistors in series and the voltage is constant, the current will decrease.
Should you obey laws that you did not create?
Yes, obey the laws and obey them well.
Does the subtraction of two vectors obey the commutative law?
Yes subtraction of vector obeys commutative law because in subtraction of vector we apply head to tail rule
