2007-08-24 10:18:02 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
The filament is made of tungsten.
2007-08-24 10:40:04 · update #1
http://www.tungsten.com/mtstung.html
2007-08-24 10:41:23 · update #2
The filament resistance is not constant. The power relationship for tungsten is:
W / 100 = (114 / 120)^n
n is 1.54 for gas filled bulbs and 1.58 for vacuum bulbs
Assuming your bulb is filled with argon, W = 92.40 Watts
For an evacuated bulb, W = 92.22 Watts
.
2007-08-24 11:08:49 · answer #1 · answered by tlbs101 7 · 4⤊ 1⤋
If the resistance were constant, the power dissipated would be 10% less, or 90 watts. (P = E^2/R.) But the resistance is not constant (it will be less at lower voltage), and the actual power used will be a bit more than 90 watts.
2007-08-24 17:26:40 · answer #2 · answered by Anonymous · 1⤊ 1⤋
ASSUMING DC [ITS EASIER TO CALCULATE USING DC]
WATTS = VOLTS X AMPS SO AMPS IS WATTS OVER VOLTS= .833333AMPS
RESISTANCE OF THE FILAMENT R = V/I = 120/.83333 = 144 OHMS
CURRENT = VOLTS OVER RESISTANCE = 114/144 =.7916 AMPS
WATTS = VOLTS X AMPS = 114 X .7916 = 90.25WATTS
SO AT 114 VOLTS DC THE SAME BULB THAT USED 100 WATTS AT 120 VOLTS WILL USE 90.25WATTS
HOPE IM RIGHT -HAVEN'T HAD TO DO THE BASICS FOR A FEW YEARS NOW!
2007-08-24 17:37:16 · answer #3 · answered by andy t 6 · 0⤊ 3⤋