Difference between lights connected in series and parallel

AI Thread Summary
When two identical lamps are connected to the same battery, they will light brighter when connected in parallel rather than in series. This is because, in a parallel configuration, each lamp receives the full voltage from the battery, resulting in higher power consumption. The power consumed by each lamp is determined by the formula P = V^2/R, where V is the voltage across the lamp and R is its resistance. In contrast, in a series connection, the voltage is divided between the lamps, leading to lower brightness. Therefore, connecting lamps in parallel maximizes their brightness due to the full voltage applied across each lamp.
prishila
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Homework Statement



When two same lamps are connected with the same battery. Their lighting will be greater when they are connected in series or parallel?

Homework Equations


Series U=U1+U2+U3+...
I=I1=I2=I3...
Parallel U=U1=U2=U3...
I=I1+I2+I3+...

The Attempt at a Solution


The answer is when they are connected in parallel. But why?
Is it related to the tension or intensity or power?
 
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In a very simple view, the brightness of a light bulb is proportional to the power it consumes. The power is determined by the voltage across the bulb and the current through it: ##P = V I##.

If you assume that the bulb has a constant resistance (again, a simple view), then Ohm's Law tells you that the current through it is related to the voltage across it by ##I = V/R##.

Use your knowledge of how voltage and current are distributed among components in series and parallel circuits.
 
gneill said:
In a very simple view, the brightness of a light bulb is proportional to the power it consumes. The power is determined by the voltage across the bulb and the current through it: ##P = V I##.

If you assume that the bulb has a constant resistance (again, a simple view), then Ohm's Law tells you that the current through it is related to the voltage across it by ##I = V/R##.

Use your knowledge of how voltage and current are distributed among components in series and parallel circuits.
So we can write P=U^2/R
U is the same in each resistance in parallel, but it divides in resistances in series. So it is greater in resistances in parallel. This way P is greater when they are connected in parallel. Am I right?
 
prishila said:
So we can write P=U^2/R
U is the same in each resistance in parallel, but it divides in resistances in series. So it is greater in resistances in parallel. This way P is greater when they are connected in parallel. Am I right?
Yes, that's a correct analysis.
 
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