will there be a difference in
brightness, will one light bulb be brighter than the other?
will one be more costly to run per currency unit per unit of electricity, than the other (given that the costs were the same for comparison purposes) ?
then, could one say that for example (like shoe sizes) that a 115volt x 100watt usa light-bulb is equal to a 230volt x 50watt light-bulb in London.?
or, if each are equally bright to read by the difference would be in the energy consumption and efficiency of the different volltages; then, which one usa or London?
I am not an electrician, but a philosopher; puzzelled by this for ages!
2007-03-24 10:24:41 · 5 answers · asked by D a n 2 in Science & Mathematics ➔ Physics
100 watts is a measure of energy expended. They are the same for both countries in your case; so the same energy is expended regardless of the voltage. As energy is what creates the heat that creates the light, and the energies are the same, the light will be the same.
If you were an engineer, you would know that watts = VI; voltage times current. Since the voltage in UK is higher, their current will be lower for the same watts as their US counterparts. Thus, in UK the filament will have a higher resistance than the 100 watt US bulb.
2007-03-24 10:45:55 · answer #1 · answered by oldprof 7 · 1⤊ 0⤋
The difference is the 230 volt bulb has a filament that that is twice the resistance of the 115 watt bulb. they both consume the same amount of wattage
2007-03-24 21:26:51 · answer #2 · answered by confused 3 · 0⤊ 0⤋
Some good answers but I must point out that "confused" is confused.
Power=V^2/R so R=v^2/Power
For 100W lamps:
London 230V resistance is about 529R and
USA 115V resistance is about 132R not half.
Also note these resistances apply at running temperature which for a filament is very hot. If you try to measure the resistance with a meter you will get much lower values.
2007-03-28 16:18:04 · answer #3 · answered by Anonymous · 0⤊ 1⤋
a watt is the light of one candle..so no matter how many volts it takes in London or in America 100watts is onehundred watts it will give off the same light.
I believe it would cost more in London because voltage is also a unit of measure like a watt...
2007-03-24 18:21:54 · answer #4 · answered by trina 1 · 0⤊ 1⤋
light output in lumens same and power consumption same
2007-03-24 17:34:50 · answer #5 · answered by koolie 1 · 0⤊ 0⤋