Max # of 60W Light Bulbs in a 30A 220V Circuit

AI Thread Summary
A 220V circuit fused for 30 amps can safely support a maximum of 30 amps multiplied by 220 volts, equating to 6600 watts. Each 60-watt incandescent bulb draws 60 watts, so dividing 6600 watts by 60 watts per bulb indicates that up to 110 bulbs can be used simultaneously without tripping the fuse. However, practical considerations such as inrush current and wiring limits may reduce this number. The discussion emphasizes the importance of understanding power calculations, specifically using the formula P = IV for determining safe load limits. Proper calculations and considerations are crucial for safe electrical circuit usage.
tDexx
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Homework Statement


A 220 volt circuit is fused for 30 amps. How many 60 watt incandescent soft whote light bulbs with tungsten filament burning at 3,0000 celsius can be used at the same time in the circuit without tripping the fuse?


Homework Equations


N/A

The Attempt at a Solution


(w/220)=30
220=30 amps(w)
220/30 amps=7.33 watts
 
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tDexx said:

Homework Statement


A 220 volt circuit is fused for 30 amps. How many 60 watt incandescent soft whote light bulbs with tungsten filament burning at 3,0000 celsius can be used at the same time in the circuit without tripping the fuse?


Homework Equations


N/A

The Attempt at a Solution


(w/220)=30
220=30 amps(w)
220/30 amps=7.33 watts

At least have a look at this:

http://en.wikipedia.org/wiki/Power_(physics)

Go to the electric power section for some useful formulae. Those same formulae will be in your textbook.
 
Unfortunately i don't have a textbook to go with my homework...
 
tDexx said:

Homework Statement


A 220 volt circuit is fused for 30 amps. How many 60 watt incandescent soft whote light bulbs with tungsten filament burning at 3,0000 celsius can be used at the same time in the circuit without tripping the fuse?


Homework Equations


N/A
In one of your other posts you listed P = IV. That would be really useful here.

The Attempt at a Solution


(w/220)=30
220=30 amps(w)
220/30 amps=7.33 watts

See above.
 
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