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Yes, the resistance of the filament of a light bulb is what generates enough heat to make the filament glow and produce light.
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Why does the filament lamp does not follow Ohms Law give any example?
A filament's resistance value varies with temperature. When directly measuring resistance, the filament is off, and at or near room temperature. When the circuit is turned on to measure voltage and current, the filament's temperature will increase and the resistance value will increase. This makes it appear as though Ohm's law is wrong.AnswerThere is no difficulty; your experiment will simply prove that the filament of the lamp doesn't obey Ohm's Law.When you plot the results of current against voltage for a lamp's filament, obtained from your experiment, the result will be a curved line, indicating that the current is notproportional to voltage (due to a changing resistance). This shows that the filament doesn't obey Ohm's Law. To obey Ohm's Law, the result must be a straight-line graph.Although the resistance of the lamp can be found at any point along the curve from the ratio of voltage to current (i.e. R = V/I) at that particular point, the lamp does not obey Ohm's Law. Ohm's Law only applies when the ratio of voltage to current remains constant throughout the experiment.So no difficulty has arisen with your experiment, you have simply proved that Ohm's Law doesn't apply to the lamp filament. Believe your results!!
Why the slope of voltage-resistance characteristic increases in the case of tungsten lamp and decresing in case of carbon lamp?
If the filament really was made from a material that has a negative temperature coefficient (as temperature increases, resistance decreases) then the decreasing resistance would cause more and more current to be taken as the lamp heated up and the temperature would get higher and higher in a runaway manner until either the power supply's breaker would trip or (more likely) the light bulb's filament would simply burn open. In fact the filament has to be made from a material that has a positive temperature coefficient. (As temperature increases, resistance increases.) Then, as the bulb's temperature rises, its filament's increasing resistance causes less current to be taken than when it was cold. Quite quickly a stable "steady-state" temperature and "running" resistance is reached so that the bulb simply continues to give out a steady amount of light according to the current it is taking from the electricity supply.
What is an incandascent lamp?
Your standard light bulb where a filament is heated by a current passing through it. The heated filament then gives off light.
Does the resistance of a light bulb filament change after the light has been turned on?
The electrical resistance of a light bulb increases when it is turned on As a resistor, the tungsten light bulb has a positive resistance coefficient. This means that the electrical resistance goes up when the filament becomes hot. For example, a 100 watt light bulb operated at 120 volts - it does not matter if it is AC or DC for this calculation - will have a resistance of 144 ohms when hot and draw .833 ampere. When cold the filament typically has a resistance of only 10 ohms which increases as the filament heats up.
Why it is not possible to determine the value of low resistance using neon flash lamp experiment?
In the neon flash lamp experiment, the resistance of the lamp is very low, often in the range of a few ohms. When measuring low resistance, the resistance of the connecting wires and contacts becomes significant and can interfere with the accuracy of the measurement. These additional resistances create uncertainties in determining the exact value of the low resistance of the lamp. Additionally, the behaviour of the neon lamp itself, which is a non-linear device, further complicated the measurement process. Therefore, it is challenging and difficult to accurately determine the precise value of low resistance using this method.
Does a lamp with a thick filament draw more current or less current than a lamp with a thin filament?
A lamp with a thick filament will draw more current. What restricts the current flow in the filament is the resistance of the filament which increases as the temperature of the filament increases. A thin filament requires less energy to get heated up that a thick one so less current to achieve threshold resistance. Also a thick filament provides a broader path for current so there is less resistance per increase in degree centigrade. For these two (closely related but distinct) reasons it will require more current for the filament to get heated up to threshold resistance.
Does a lamp with a thick filament draw more or less current than a lamp with a thin filament?
A lamp with a thick filament will draw more current. What restricts the current flow in the filament is the resistance of the filament which increases as the temperature of the filament increases. A thin filament requires less energy to get heated up that a thick one so less current to achieve threshold resistance. Also a thick filament provides a broader path for current so there is less resistance per increase in degree centigrade. For these two (closely related but distinct) reasons it will require more current for the filament to get heated up to threshold resistance.
Why is the filament inside an electric lamp made very fine?
The filament is fine so that its electrical resistance can be quite high. It is also long, for the same reason. Usually it is coiled up to fit the length in the lamp. The heating effect of electric current is proportional to the current squared, time the resistance (I*I*R). Most of the effect is due to the current. The current through the filament must be limited to stop it melting. Adding resistance will do that. Taking resistance away increases heating. So, a low energy lamp has a very thin filament and a high energy lamp will have a thicker filament.
Why is there a curve and not a straight line in the graph for a filament lamp?
I had to answer this and found out that............ The line on the graph that represents the filament lamp is curved because the resistance of it increases with supplied voltage Hope this is alright for you :) x
What is nonlinear resistance?
A nonlinear resistance is a resistance which is different for different voltages ie current is not proportional to voltage. An example of this is the filament of an incandescent lamp.
WhY does a filament lamp get when you us high voltage?
because there is a correlation between resistance and voltage and current. The equation resistance = voltage divided by current shows that the higher the voltage, the bigger the resistance,, and the bigger the resistance the hotter the filament lamp will get because of the electrons bumping into each other which means there is a loss of energy and that energy is being transferred to the filament making the actual filament bulb hot since there is more thermal energy wasted at the end.
What happens to the energy when you turn on an electric lamp?
Electricity flows through the filament, resistance in the filament causes heat and light energy to be created.
Why does a filament lamp get hot when you use high voltage?
because there is a correlation between resistance and voltage and current. The equation resistance = voltage divided by current shows that the higher the voltage, the bigger the resistance,, and the bigger the resistance the hotter the filament lamp will get because of the electrons bumping into each other which means there is a loss of energy and that energy is being transferred to the filament making the actual filament bulb hot since there is more thermal energy wasted at the end.
Graph of resistance of filament lamp against potential difference?
It will vary from 0 to a certain value but at a slower rate.
Why does the filament lamp does not follow Ohms Law give any example?
A filament's resistance value varies with temperature. When directly measuring resistance, the filament is off, and at or near room temperature. When the circuit is turned on to measure voltage and current, the filament's temperature will increase and the resistance value will increase. This makes it appear as though Ohm's law is wrong.AnswerThere is no difficulty; your experiment will simply prove that the filament of the lamp doesn't obey Ohm's Law.When you plot the results of current against voltage for a lamp's filament, obtained from your experiment, the result will be a curved line, indicating that the current is notproportional to voltage (due to a changing resistance). This shows that the filament doesn't obey Ohm's Law. To obey Ohm's Law, the result must be a straight-line graph.Although the resistance of the lamp can be found at any point along the curve from the ratio of voltage to current (i.e. R = V/I) at that particular point, the lamp does not obey Ohm's Law. Ohm's Law only applies when the ratio of voltage to current remains constant throughout the experiment.So no difficulty has arisen with your experiment, you have simply proved that Ohm's Law doesn't apply to the lamp filament. Believe your results!!
What part of the lamp converts electricity to light?
For a filament-type (incandescent) lamp, it's the filament.
If the tungsten filament of a lamp has a cross-sectional are of 5x10-9 m2 how long must it be have a resistance of 120 ohms at 20 degrees Celsius?
If the tungsten filament of a lamp has a cross-sectional area of 5x10-9m2,how long must it be to have a resistance of 120 ohms at 20 degree celsius?
