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
Messages
3
Reaction score
0
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?
 
Physics news on Phys.org
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?
 
Last edited:
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?
 
Thread 'Question about pressure of a liquid'
I am looking at pressure in liquids and I am testing my idea. The vertical tube is 100m, the contraption is filled with water. The vertical tube is very thin(maybe 1mm^2 cross section). The area of the base is ~100m^2. Will he top half be launched in the air if suddenly it cracked?- assuming its light enough. I want to test my idea that if I had a thin long ruber tube that I lifted up, then the pressure at "red lines" will be high and that the $force = pressure * area$ would be massive...
I feel it should be solvable we just need to find a perfect pattern, and there will be a general pattern since the forces acting are based on a single function, so..... you can't actually say it is unsolvable right? Cause imaging 3 bodies actually existed somwhere in this universe then nature isn't gonna wait till we predict it! And yea I have checked in many places that tiny changes cause large changes so it becomes chaos........ but still I just can't accept that it is impossible to solve...
Back
Top