Would an average light bulb last longer if left on continuously instead of on and off continuously?

Question

The reason I wonder is the bulbs in my bathroom state they last about 1500 hours. I know we use them only about 2-3 hours a day which would put to last over a year and I know they don't last that long . I know I can buy the longer lasting bulbs but is the industry lying about how long the low end bulbs last or is it based on being left on?

Answer 1

The life of a light bulb is usually reported in terms of a test where the bulb is left constantly on. But the total cumulative lifetime would indeed be shorter when the bulb is turned on and off in the course of normal usage. Each time you turn a bulb on, it gets a power surge. A light bulb almost always burns out as a result of such a surge; notice that bulbs usually flash and burn out when you turn them on, rather than burning out while they're already on.

Answer 2

1

Answer 3

there are answers for both the incandescent light bulbs and the fluorescent light bulbs. you did not specify which. there are other types of light bulbs, but these two are the most widely available types.

it would be very costly to perform laboratory controlled experiments to determine what's best for you.

i've been wondering about whether the incandescent round bulbs or the fluorescent coiled ones that fit in the space for the round incandescent bulbs are the greatest value, because at times I can get those flourescents for about the same price as the incandescents. my general finding is that a number of both the incandescents and flourescents have very short lives, which I suspect is due to quality assurance problems. i'm still experimenting, and hoping the flourescents generally last at least as long as the incandescents because they often cost the same per bulb, while the flourescents require many less watts to give off the same amount of life as the incandescents.

you might want to try what I'm trying and see if it works out for you.

Answer 4

Heating and cooling anything will cause it to expand and contract, so it will remain stable longer in a constant state. Take two rubber bands> Stretch one around something, and just leave it like that. Stretch the other to an equal tension every day. The static one will have to rot before failing, but the second will become unstable rather quickly, develop fractures and snap. The same effect seems to apply to any physical material, such as a tungsten filament. Mythbusters is entertainment, not science.

Answer 5

Not exactly what you asked, but-
Try installing the new Compact florescent light bulbs; the energy savings will pay for the bulb in about one year. And they last a LOOOng time- maybe 5 years

Answer 6

The filament heats-up / cools-down and expands / contracts each time the power is turned on / off. The result is metal fatigue. So the answer is the bulb would have a shorter operating life if turned on and off.

Answer 7

The power surge that occurs when turning the light bulb on probably weakens the filament.

Answer 8

nicely it would want to quite count number on how i'm about to die. If i'm about to be murdered or if this is surprising i might want to ask for 5 minutes to imagine about my existence, the human beings in my existence, and that i might want to prey. If this is yet differently and that i have a strong era of time i might want to search for suggestion from with the human beings i appreciate and note them one very last time.

Answer 9

they did a test on mythbusters and they proved that it only saves you about .34 secs to leave the light on instead of turn it off so it doesnt relly matter

Answer 10

I think this is caused by the rapid change in temperature of the filament.