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If A Light Bulb Burns Out But The Switch Is Still On Is The The Circuit Still Consuming Power

15 or twenty years ago it would have been a slam dunk answer: NO. But there’s new technologies so the answer has to be qualified.An old-style incandescent bulb has a simple single resistive element that glows and emits light when powered. In a burned out incandescent bulb the resistor becomes an open circuit and as such no power will flow or current be used. No power or energy is wasted therefore.In the newer lamp types, we have CFL and LED bulbs. They consist of a power conversion circuit that provides power to the illuminating element. If the illuminating element breaks or fails, it is possible that the circuit will continue to operate and waste some power and even a failed illuminator may draw power. There’s so many types and failure modes that its impossible to predict.If the entire bulb is missing and the socket is empty, then we’re back to the original slam dunk: No. the socket is an open circuit and no current or power flows.

Does a burned out lightbulb still use electricity if switch left on?

Ok, Basic electricity :
With out a completed circuit, the appliance will not use electricity.
Each bulb consumes or uses amps when it is actuated, so naturally burnt out bulbs will not use any, so the fixture will use less electricity.
T.V.'s today are almost all remote controlled, so they are in standby mode. This means that they are partially on and just waiting to actuate the screen when you hit the on button. So these will use almost as much juice in hibernate as when active.

Most kitchen appliances, toaster, mixers, crock pots, do not use anything until turned on. I f they have a clock or a light that stays on, then they are drawing power all the time.

Just to clarify, a 60 watt bulb cost about .08 cents and hour to run, so 8 of them would be.....64 cents per hour, and if a train left Kansas traveling at 60 MPH.... simple math stuff.

If you are concerned about power consumption, change to the CFC bulbs. Besides costing less to operate, they do not generate near the heat of regular incandescents, so make it cheaper to keep your house cool in the summer.

If a lightswitch is on but the light bulb is burned out does it still use electricity?

a lightbulb that is burned out is no different than if you removed the bulb completely, i dont know what little arc in the bulb that other answer is talking about, but there is no such thing, a light bulb that is burned out DOES NOT USE POWER. if they do then why do your christmas lights go out when one of the bulbs blow? if you are talking about a fluorescent light then the ballast will use some power, but not incandescent. you do not pay for electricity being in your wires, you pay for USING it to run something. flipping on the light switch costs you nothing unless it turns on a bulb, not a blown bulb, a working bulb. apparently people who know nothing about electricity decided to answer this question and are now upset they are wrong. ask any electrical engineer you want how electricity works.

How many lightbulbs can run on this circuit?

Use this helpful formula

Power=voltage x current

or P=VI
you are already given the power, and maybe the voltage can be assumed to be 120volts AC?

so now you have the V and the P so you calculate the I for one light bulb. This will tell you the current (in amps) one light bulb consumes and you are trying to get to 20amps so this should be a simple calculation.

Lets take two cases: older incandescent buls and newer electronic bulbs - namely CFLs and LEDs. And lets say failed indicates a lack of light output, either completely out or a incorrect amount.The first case is the classic incandescent.In the case of an incandescent, they really only have one working part, the filament, and it will either break or the failure of the glass or the harp will cause it to break. When it breaks, no current flows so it cannot use electricity.The other case is electronic bulsb. CFLs and LEDs.CFLs and LEDs can fail while still drawing some current.They are complex electronic devices consisting of AC/DC power supplies to power the light circuits.The reason they can still draw power is the power supply components or the light driver circuit may still be active or have failed in some current drawing way even if the light emitting element is burned out, This is one of the disadvantages of new high efficiency lighting - it is so much more complex than the simple filament-is-the-only-part incandescent.As an aside, I once found a dead (as in “not emitting light”) CFL actually pulling more current than its listed electrical rating. I would say that this is not the normal case. Usually a failed bulb would use less than rated current or no current at all.

For current to flow in a circuit the circuit must be closed. If there is no light bulb in the socket the current cannot flow across this gap in the circuit, therefore no electricity is being used.If the circuit is designed such that the light socket is in parallel to the power supply then there may be another node for the electricity to flow through, however as there is no "load" then you have a short circuit. This means that the electricity flows from the source, around the wires, and back to the source. This isn't good! You may end up with melted wires or the power source blowing up. When there is no resistance to the flow of charge carriers you get a very high current, a large amount of energy is transferred in a very short amount of time. This large amount of energy needs to go somewhere, either back to the source or transformed in the wires as heat energy. In your home you will find a circuit breaker. This provides protection in the event of high current flow, and will break the circuit and stop the flow of current.Alternatively you may find if you are using a lamp with a plug, the plug may be fused (depending on the country you live in), this fuse in the plug has a small piece of wire inside that is rated for a certain amount of current. If there is a short circuit and the current goes above the rated limit, then the wire inside the fuse melts - stopping the flow of current.

Incandescent bulbs will virtually and quickly go to an open state when failed (assuming busted here means either the glass broken or the filament failed. ) When open they draw no power.LEDs and CFLs are a different story. They have some electronics in between the power input and the lighted element and if the electronics fails then the unit may possibly draw power even if no light is emitted (a liberal interpretation of “busted”). If your term busted means the globe diffuser over the LED, then that will have little or no impact on the power but may affect the way the light is diffused. If you break the curly-cue of the CFL, it probably will not light but will still draw power to try and run the ballast.I have found this to be true as I replaced a burned out CFL and found it to warmer than it should have been having gone out some time previously. I measured it with my power meter and sure enough it was drawing more power than it should have even when it was working.I will say this is rather rare but not impossible. Most failed CFL and LED will draw little or no power when they go out.

Does a broken light bulb consume electricity if it is screwed into a light socket and the light switch is on?

Short answer No.

Because it is open circuit when broken or removed it wont pass any current therefore wont consume any electricity.

You may find that the 5 globe light hardly ever has all 5 globes working at once because 1 always seems to be blown?

If this is the case try putting in just 2 or 3 higher wattage globes instead of 5 and you will find they will last longer. This is because the fillaments in higher wattage globes are stronger.

So if your light uses say 5 x 40 watt globes, this is 200 watts total. Take out the 5 x 40 watt globes and try putting in 2 x 100 watt globes. The light output will be the same and the globes will last longer. Try it!

Does it use electricity if you turn the light switch on without having a light bulb in?

Good idea. No if a bulb is not powered it doesn't draw electric. Another awesome option is LED lighting. We changed all our bulbs to LED's and our electric bill went from $150 down to $95! I found the most quality bulb for the best price at Energy Innovations 877- NRG-SOLUTIONS. They also stand behind their bulbs for 3 yrs. Ihate the CFL's because they have mercury and also are not as efficient and don't last as long. These LEDS last 50000 hours and for a 50 watt equivalent only runs on 5 watts! Best of all they look like the incandescents basically so I love them!