Relative Brightness of Light Bulbs in Series & Parallel Connection

AI Thread Summary
In the given electrical circuit with five identical light bulbs, light bulbs A and B are connected in parallel, while bulbs C and D are in series and connected in parallel with bulb E. The discussion concludes that the brightness of the bulbs can be analyzed by considering the current distribution and voltage across each branch. It is established that A and B will have equal brightness, as will C and D combined with E, leading to the conclusion that A = B = E = C + D. The key takeaway is that the distribution of current determines the relative brightness of the bulbs, with the brightest bulb receiving the most current.
Empire
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Assuming there are five identical light bulbs. Light bulb C and D are in a series connection. C and D are in a parallel connection with E. Light Bulb A and B are in a parallel connection. The two parallel connections are wired in a series connection. What would be their relative brightness? I'm thinking that A=B=E=C+D

********************
|----power---------------|
|*******************|
|*******************|
|**|--A--|***|-C-D-|**|
|---|****|----|****|---|
***|--B--|***|--E--|***
********************


in a parallel connection, It=I1+I2, therefore, A=B. In a seriese connection, The total current equals the individual currents, so C=D. Back to the parallel connection, C+D=E. In a series, they are all equal, so (A+B)=(E+C+D). Therefore...A=B=E=C+D. My friend said that it might be: C^D<A^B<E

Any suggestions?
 
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EDIT: Ignore this post! I misread your diagram; Chi Meson has it right in the next post.

Empire,

Think of it more as an electrical problem first, and then worry about brightness.

Suppose your power source is a voltage of 100V.

What's the voltage across the B-E branch?

So what's the voltage across B? Across E?

What's the voltage across the A-CD branch?

So What's the voltage across A (be careful!)? Across CD ? Across C? Across D?
 
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Another way to think of it: The brightest bulb will have the most current going through it.

Obviously,the total current through the entire A/B unit will equal the total current through the C/D/E unit. And the current through A and B is equal, and each gets exactly half the total current.

So ask yourself, where will more current go, through the C-D branch, or the E branch?
 
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