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quantum123
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What does the brightness of a bulb depend on: power or current?
KingNothing said:Maybe you should do an experiment: hook up a bulb to a constant voltage source, and vary the current while holding power constant.
Bloodthunder said:Can't do that. P = IV, so if V is constant, whatever changes you make to I will change P as well.
KingNothing said:Yes...that was my point :). To make the original poster see the silliness of his or her question.
Physicist1231 said:I'm not that great with electronics but doesn't have something to do with how much resistance the filiment is able to take? The more current you put into a filiment the brigher but at the same time if you put the same current into a more resistant filiment it too would be brighter?
Of course it may not last as long but still. Just curious about that one. Any ideas?
quantum123 said:Imagine you put up a voltage of 1,000,000 volts, but only allow one electron to pass through per second. Will the lamp be bright?
quantum123 said:Imagine you put up a voltage of 1,000,000 volts, but only allow one electron to pass through per second. Will the lamp be bright?
quantum123 said:What does the brightness of a bulb depend on: power or current?
quantum123 said:Imagine you put up a voltage of 1,000,000 volts, but only allow one electron to pass through per second. Will the lamp be bright?
AtomicJoe said:No.
Power is I^2 R. The resistance is fixed, for one electron the current is tiny.
Any experiment to achieve this would be to put the voltage across a brick in series with the bulb, or alternatively leave the bulb switched off!
SpectraCat said:Hmmm .. you are right in practice of course, but in principle V=IR, so P=IV, which implies that even for a current of 10^-18 Amps (which is about 1 electron per second), a 60 W bulb would glow if you ran the current at a potential difference of 60x10^18 Volts. The issue is that such high voltages are not achievable in practice. However, in principle it shouldn't matter if he runs the bulb at 1 mA and 60 kV, or 1 A and 60 V. Both amount to 60 W, and so should produce the same brightness.
quantum123 said:Pleae note that resistance is not constant, as the tungsten filament is not Ohmic.
The brightness of a bulb is directly proportional to the power and current passing through it. This means that as the power and current increase, the brightness of the bulb also increases.
The power of a bulb is a measure of how much electrical energy it consumes. A higher power bulb will consume more energy and produce a brighter light compared to a lower power bulb.
Yes, the brightness of a bulb can be increased by increasing the current passing through it. This is because the current is responsible for heating the filament in the bulb, which in turn produces light.
Yes, there is a limit to how much power a bulb can handle. If the power exceeds this limit, the bulb will overheat and burn out. It is important to use the correct wattage bulb for the intended fixture to prevent damage.
The type of bulb, such as incandescent, fluorescent, or LED, can affect its power and brightness. LED bulbs, for example, are more energy-efficient and produce brighter light than incandescent bulbs with the same power rating.