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How can a filament give off heat without resistance?
Another Answer
The terms, 'ohmic' and 'non-ohmic' refer to whether or not a material obeys Ohm's Law. It has NOTHING to do with whether a filament is resistive or not!
Ohmic materials obey Ohm's Law; non-ohmic materials do not.
GSL incandescent lamps generally use a filament made of tungsten. If you were to apply a gradually-increasing voltage to that filament, and note the corresponding values of current and, then, plot the results in the form of a graph, you would find that the graph is a curve. For Ohm's Law to apply, the current must be proportional to voltage for variations in voltage and this is ONLY true for a straight-line graph. Tungsten, therefore, is non-ohmic and does not obey Ohm's Law.
Tungsten is chosen for lamp filaments because it can withstand very high temperatures without failing. This is the main reason that it is chosen, NOT because it is non-ohmic.
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How does the graph vary between voltage and current?
If the graph is for Ohmic components e.g resistor or wires -Constant gradient -V is proportional to I The second graph is for Non-Ohmic components e.g Filament lamps/diodes -(v is NOT proportional to I) -Gradient is high at the origin (0,0) and low at the top due to an increase in resistance Hope this helps!! I couldn't put the pictures on, but just google a Filament lamp graph and they will come up :)
Why is an incandescent lamp nonlinear?
Because the more you heat up a conductor the more it's electrically resistant. So, when you increase the supply voltage across such a lamp, the current increases as well, but it heats up the filament, which in turn lowers the current. So, its current depends on 2 variables: voltage and filament temperature. That's why you find a discrepancy between the resistance you measure with an ohmmeter and the one you calculate by using its rated power.
How do you differentiate a metal from a nonmetal using instrument?
A metal conducts heat better than a nonmetal. If you put a metal and a non-metal in boiling water for the same amount of time, the metal will be hotter than the non-metal. If you put a metal and non-metal in ice water for the same amount of time, the metal will be colder than the non-metal. Also, metal conducts electricity better than non-metal. You can use metal and non-metal wires to conduct a battery, and see which one works better.
What is the mobility of the eubacteria?
Eubacterium may either be motile or non-motile. If they are motile, they will have a flagellum. Their typical flagellum will have a basal body, filament, and hook.
What are the quantities involved in Ohm's law?
-- Voltage between two points-- Resistance of the conducting path between the same two points-- Current that flows between the two pointsAnswerThere are two quantities involved with Ohm's Law: potential difference and current. For a circuit to obey Ohm's Law, the ratio of potential difference must be constant. Not many circuits obey Ohm's Law. Those that do, are called 'linear' or 'ohmic' circuits; those that don't are termed 'non-linear' or 'non-ohmic'.
Is vacuum tube ohmic or non-ohmic and why?
Vacuum tubes are non-ohmic devices
Is Thermistor ohmic or non-ohmic?
no.....thermistors are not ohmic.
Differentiate between ohmic and non ohmic substances?
which law follow non ohmic substances
What are ohmic and non - ohmic conductors?
ohmic conductor does obey ohm 's law. non ohmic conductor does not obey ohm's law.
Is a light bulb an ohmic conductor?
For a material to be 'ohmic' or 'linear', it must obey Ohm's Law. For Ohm's Law to apply, the ratio of voltage to resistance must be constant for variations in voltage. An incandescent lamp's filament is manufactured from tungsten, which is 'non-ohmic' or 'non-linear' because the ratio of voltage to current changes for variations in voltage. In fact, MOST conductors and electrical devices (such as diodes) are non-ohmic. If you were to conduct an experiment that allowed you to record the variation if current flowing through a tungsten filament for variations in voltage, the result would be a curved graph line -in other words, a 'non-linear' (therefore, 'non-ohmic'), graph line. So, to directly answer your question, NO, a tungsten filament is not an ohmic material.
What is the difference between an ohmic resistor and a non-ohmic resistor?
A non-ohmic resistor doesn't have a constant resistance. A ohmic resistor has a constant resistance.
Example of non -ohmic and ohmic materials?
iron,gold
What is the difference between ohmic and non ohmic elements?
An 'ohmic' resistor is one which obeys Ohm's Law. For Ohm's Law to apply, the resistance of a circuit must be constant over the range of incremental voltages applied to it. If the resistance changes over an incremental range of voltages, then it is said to be 'non-ohmic', and it does not obey Ohm's Law.
What are Ohmic and Non - Ohmic conductor?
ohmic ocnductor is a material which obeys ohm's law: i.e. the voltage and current are directly proportional 2 each other anda non-ohmic ocnductor is a material which doesn't obey ohm's law:)
What are non ohmic resistances?
your dad
When the voltage across the ends of a piece of wire is doubled what effect does this have on the current in the wire?
current doublesAnswerIt depends on whether the wire is ohmic or non-ohmic. If it is ohmic, then the current will also double. If, like tungsten, it is non-ohmic, then it depends.... because doubling the voltage will cause its resistance to increase.Ohmic materials obey Ohm's Law, whereas non-ohmic materials do not.
How does the graph vary between voltage and current?
If the graph is for Ohmic components e.g resistor or wires -Constant gradient -V is proportional to I The second graph is for Non-Ohmic components e.g Filament lamps/diodes -(v is NOT proportional to I) -Gradient is high at the origin (0,0) and low at the top due to an increase in resistance Hope this helps!! I couldn't put the pictures on, but just google a Filament lamp graph and they will come up :)
