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No. For Ohm's Law to apply, the ratio of voltage to current must remain constant for variations in voltage. This simply doesn't happen with a tungsten filament. In fact, MOST materials don't obey Ohm's Law.

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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?

To find the length of the tungsten filament, you can use the formula: R = ρ * (L/A) Where R is the resistance (120 ohms), ρ is the resistivity of tungsten, A is the cross-sectional area (5x10^-9 m^2), and L is the length of the filament. Rearranging the formula to solve for L gives: L = R * A / ρ Given the resistivity of tungsten at 20 degrees Celsius, you can calculate the length of the filament.


What is the resistance of a domestic filament lamp?

Voltage squared equals current times resistance, so voltage squared divided by power equals resistance. So, for a 60W bulb: * (120V)^2 / 60 = R * 14400 / 60 = 240 ohms Keep in mind this is after the bulb reaches operating temperature. The resistance of the filament is temperature dependent.


What does thirty five degrees Celsius convert to in ohms?

Temperature in degrees Celsius cannot be directly converted to ohms as they are different units of measurement. Ohms are used to measure electrical resistance whereas degrees Celsius measure temperature.


In parallel circuit whathappens to the total resistance if one branch opens-Provide an example?

In a parallel circuit, each load added subtracts from total resistance. When one or more loads is removed from a parallel circuit, the total resistance is increased, reducing the total amperage draw. The less resistance a load has, the more current can pass through. This is part of Ohm's law. The mathematical equation that describes Ohm's law is: I=V/R , where I is the current in amperes, V is the potential difference in volts,and R is a circuit parameter called the resistance For example : The humble light-bulb is rated by the watts it uses. The amount of watts used by a light-bulb is calculated using Ohm's law. With the resistance of the bulb's filament and the voltage the bulb is designed to operate with, one can derive the amperage the bulb will draw. The amperage is then multiplied by the voltage to show wattage. Using Ohm's law : With the resistance of a 40watt 120volt light-bulb, only 0.33amps is able to pass through the bulb's 363ohm filament at 120volts. A lamp that has two 40watt bulbs inplace, and the two bulbs are in parallel, the circuit will have a resistance of 179ohms and draw 0.67amps which is 80watts at 120volts.


What does 425 degrees Fahrenheit to in ohms?

Temperature (in degrees Fahrenheit) cannot be directly converted to resistance (in ohms), as they are different units of measurement. Temperature is a measure of thermal energy, while resistance is a measure of opposition to electric current flow in a circuit.

Related Questions

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?

To find the length of the tungsten filament, you can use the formula: R = ρ * (L/A) Where R is the resistance (120 ohms), ρ is the resistivity of tungsten, A is the cross-sectional area (5x10^-9 m^2), and L is the length of the filament. Rearranging the formula to solve for L gives: L = R * A / ρ Given the resistivity of tungsten at 20 degrees Celsius, you can calculate the length of the filament.


Why does the filament lamp does not follow Ohms Law give any example?

Well, honey, the filament lamp doesn't give a hoot about Ohm's Law because its resistance changes with temperature. As the current increases, the temperature of the filament rises, causing the resistance to also increase. It's like trying to control a wild horse - good luck getting it to follow any law!


Is ohms law applicable to 60 watt bulb?

Ohm's Law doesn't apply to an incandescent lamp, regardless of its power rating. This is because the filament is manufactured from tungsten which is a 'non-ohmic' or 'non-linear' conductor, which means that the ratio of voltage to current changes for variations in voltage. For Ohm's Law to apply, this ratio must remain constant for variations in voltage.


What happen if a 110 volt lamp connected on a low voltage?

If you had a 60 watt incandescent bulb it would draw about 1/2 amp. That means that the resistance of the bulb filament would be about 220 ohms. Now if you applied 12 volts DC across 220 ohms you would draw about .05 amps. This would not be enough to heat the filament and create any useful light. Remember Ohm's Law says Volts = Amps x Ohms.


What is meant by cold resistance of filament lamp?

It means exactly what it sounds like. The resistance of an incandescent bulb's filament depends on its temperature. A filament has a positive temperature coefficient, which means that its resistance increases as its temperature increases. A typical 40 watt bulb (120 volts) has a cold resistance of about 28 ohms, but its hot, operating resistance is about 360 ohms. If the cold resistance were constant, the bulb would dissipate 379 watts. In fact, cold turn on is the most stressful time for a bulb.


What is the resistance of a domestic filament lamp?

Voltage squared equals current times resistance, so voltage squared divided by power equals resistance. So, for a 60W bulb: * (120V)^2 / 60 = R * 14400 / 60 = 240 ohms Keep in mind this is after the bulb reaches operating temperature. The resistance of the filament is temperature dependent.


Where you r not apply ohms law?

in transformer


What difficulty will Aries while testing wheather the filament of light bulb obeys ohms law?

If you plot a graph of current against a range of voltages applied to an incandescent lamp, the result will be a curvedline. This tells us that the current is not proportional to the voltage and, so, the lamp does not obey Ohm's Law.However, the ratio of voltage to current will indicate the resistance for that particular ratio.


What is the resistance of 150-volt lamp with a current of 2amps?

75 ohms. R = E/I.


Can you use a 24 volt lamp in a 12 volt socket?

Let's say you have a 60 watt bulb. At 120 VAC that bulb will draw 1/2 amp. By Ohm's Law: Volts = Current x Resistance. Therefore, the resistance of the bulb filament is 240 Ohms. If 12 volts is applied across 240 Ohms the current = 12/240 or 1/20 of an amp. This small current will not be sufficient to heat up the filament and provide useful light. You might see a small glow in a dark room.


Why do the reading differ for increasing and decreasing values of the lamp voltages?

at the time of decreasing lamp voltage as the temperature is already high the gas in the lamp is already in ionized state leading to different resistance ,but when increasing voltage the gas is not in ionized state it ready to ionize ,so there is slightly variation in resistance . :)


How does one practically apply ohms to amplifier vs speakers?

the watts for 2 ohms is more than 4 ohms. depending on the ohms your speakers take up and the wattage the speakers use, tells you what size amp you need.