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That depends on what voltage it's designed to operate from.
Power = (voltage)2 / R
R = Voltage2 / power
If it's a 117-volt bulb, R = (117)2 / 28 = 489 ohms.
If it's a 240-volt bulb, R = (240)2 / 28 = 2,057 ohms.
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∙ 12y ago
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What is the resistance of a 40 watt bulb?
On this calculation I am assuming that the light bulb is using a 120 volt source. Watts = Amps x Volts. Amps = Watts/Volts, 40/120 = .33 amps. R = Volts/Amps, 120/.33 = 363.6 ohms resistance in the 40 watt light bulb.
Why is 60 watts written on the bulb?
It is probably a 60 watt bulb (believe it or not). Bulbs are rated in watts. A 100 watt bulb is brighter and consumes more power than a 60 watt bulb
Is a watt a light bulb?
A 60 watt light bulb is a light bulb with 60 watts capacity. When talking about watts, you're talking about the power that is transferred from the appliance to the accessories. Therefore, the light bulb labeled "60 watts" takes 60 watts to light up. A 60 watt light bulb will not be as bright as a 120 watt light bulb.
Which has the thickest filament - a high-resistance or a low-resistance bulb?
A low resistance bulb has a thicker filament.
Was James Watt the first to invent the light bulb?
no
For bulbs connected in series the high watt bulb has high resistance?
No, the highest wattage bulb will have the lowest resistance.
What does a light bulb have?
The resistance of a light bulb varies, depending on the type of bulb, the power rating, and the temperature. A typical incandescent 60 watt bulb, for instance has a cold resistance of about 30 ohms, and a hot resistance of about 240 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.
Which has a higher resistance a 5w lamp bulb or a 25w lamp bulb and how many times?
As per the formula for power (Power (Watt) = Voltage (V) x Current (i) & Resistance (R) = V / i), 25w lamp bulb would have higher resistance compared to that of 5w lamp bulb.
What is the resistance of a 40 watt bulb?
On this calculation I am assuming that the light bulb is using a 120 volt source. Watts = Amps x Volts. Amps = Watts/Volts, 40/120 = .33 amps. R = Volts/Amps, 120/.33 = 363.6 ohms resistance in the 40 watt light bulb.
A 60-watt 120 volt lamp requires morecurrrent than a 40 watt 120 volt lamp?
Yes. A 60W bulb has a higher resistance than the 40W buld. The extra resistance requires more current to light up the bulb. The fillament then glows brighter.
Can A 70 watt metal halide bulb be replaced with A 150 watt halide bulb?
No. A 70 Watt metal halide bulb can not be replaced with a 150 Watt halide bulb.
If 200 and 600 watt bulbs are fed with a same voltage source then the resistance of 200watt bulb when compared to 600watt bulb?
The resistance of the bulbs doesn't depend on the voltage source. They can be wrapped in tissue in cardboard boxes in the drawer. If one bulb is designed to dissipate 200 watts and another is designed to dissipate 600 watts when they're both energized by the same voltage, whatever that is, then the 200-watt bulb has three times the resistance of the 600-watter.
The problems of electricity two light bulbs of 100 watt and one 60 watt both operation in a 220V circuit. Which bulb has the higher resistance and which bulb carries the greater current?
A 100 watt 220 volt light bulb (or anything consuming 100 watts on 220 volts) draws 100/220, or .45 Amps. It will also have about 220²/100, or 484 ohms resistance. A 60 watt 220 volt light bulb (or anything consuming 60 watts on 220 volts) draws 60/220, or .27 Amps. It will also have about 220²/60, or 807 ohms resistance.
Which has a more resistance a 100 W bulb or a1000 W heater?
The resistance is equal to the voltage-squared divided by the power. So a 1kW heater is 52.9 ohms, a 100 watt bulb is 529 ohms. The basic formula is W = V^2 / R
Can I use a 60 watt bulb in a 75 watt bulb ceiling fan?
Yes.
Where do you find a watt?
A watt is a measurement of electricity, usually pertaining to light. Light bulbs luminosity is graded by wattage, such as a 60 watt bulb, 100 watt bulb and so on. You would find a watt in a light bulb, to start.
