A household circuit rated at 120 Volts is protected by a fuse rated at 15 amps. What is the maximum number of 100 watt light bulbs?
A household circuit rated at 120 Volts is protected by a fuse rated at 15 amps. What is the maximum number of 100 watt light bulbs which can be lit simultaneously in parallel in this circuit without blowing the fuse?
- billrussell42Lv 76 months agoFavorite Answer
one bulb draws a current of
P = EI
100 = 120I
I = 100/120 = 5/6 amp
15 amps / (5/6 amp/bulb) = 15•6/5 bulb = 18 bulbs
(this is school problem answer)
but fuses and bulbs have tolerances, so you need to reduct that to 16-17
- Sean KLv 56 months ago
The electrical code says 12.
- M.Lv 76 months ago
My selfish, safe, personal opinion is:
15 amp, 14 gauge wiring, times 80% equals 12 continuous amps, 24 hours per day.
Pretending that there is a true 100 watt bulb and 120 volts, such a bulb will draw .8333 amps.
So, 12 usable amps divided by .8333 amps equals 14.4 bulbs.
So MY answer is 14 bulbs.
24/7. No overload.
1400 watts total.
- charlatanLv 76 months ago
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- 6 months ago
18 100 watt light bulbs
- 異域秦後人Lv 76 months ago
18 pieces 100w light bulb.