Rank Bulbs A-F: Brightest to Dimmest

In summary, the conversation is discussing the ranking of brightness for six identical bulbs connected to an ideal battery. In order to determine the brightness, the current in each bulb needs to be calculated in terms of bulb resistances, considering the effect of other bulbs. The formula for resistors in series and parallel can be used to find alternative diagrams with new resistances representing combinations of bulbs. Further analysis is needed to compare the current in bulb A to bulb D. It is assumed that the bulbs act like resistors.
  • #1
skli
3
0
The figure shows six identical bulbs connected to an ideal battery. All the bulbs are glowing
Please see attached file.
Rank in order, from brightest to dimmest, the brightness of bulbs A to F.
Thank you

copy from Physics for Scientists and Engineering with Modern Physics by Randall D. Knight.
 

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  • #2
show ur attempt.
or, are you trying to check us??
 
  • #3
OK - you get a little hint:
You need to figure the currents in each bulb, not in amps, but in terms of bulb resistances.
The current in D is going to be affected by everything that goes on with B, C, E, F.
Before you can get that right, realize you need to figure what C and E look like taken together.

You have a formula for resistors in series and in parallel. Figure out some alternative diagrams with new resistances representing the combinations of bulbs. Look at the branches, and figure that a current arriving has to split, being shared between the resistances with the most share going to the arms with the lower resistances in inverse proportion

Start off by thinking about bulb A compared to bulb D. Come back with what you have.
 
  • #4
Just a side note: light bulbs have negative resistance and hysteresis. If your teacher did not specify, my guess would be that you are to assume the bulbs act just like resistors.

We do need some evidence that you have tried to solve the problem, or at least some questions from you that indicate you are thinking about it, before we can help much more than by giving you the theory.
 

FAQ: Rank Bulbs A-F: Brightest to Dimmest

What is the basis for ranking bulbs from brightest to dimmest?

The ranking of bulbs from brightest to dimmest is based on their luminous efficacy, which is a measure of how efficiently a bulb converts electrical energy into visible light. The higher the luminous efficacy, the brighter the bulb will be.

How are bulbs measured for their brightness?

Bulbs are measured in lumens, which is the amount of visible light they emit. The higher the number of lumens, the brighter the bulb will be. This measurement takes into account the entire range of light emitted by the bulb, not just the visible spectrum.

Are there any other factors that affect a bulb's brightness?

Yes, there are other factors that can affect a bulb's brightness, such as the color temperature and beam angle. The color temperature refers to the color of the light emitted by the bulb, with higher color temperatures producing a cooler, bluer light and lower color temperatures producing a warmer, yellower light. The beam angle refers to the spread of the light, with narrower angles producing a more focused beam and wider angles producing a more diffuse light.

Is the ranking of bulbs from brightest to dimmest consistent across all types of bulbs?

No, the ranking of bulbs from brightest to dimmest can vary depending on the type of bulb. For example, LED bulbs typically have a higher luminous efficacy than incandescent bulbs, so an LED bulb may be ranked as the brightest in its category, but not necessarily compared to all types of bulbs.

Can the ranking of bulbs from brightest to dimmest change over time?

Yes, the ranking of bulbs from brightest to dimmest can change over time as new technologies and advancements are made in the lighting industry. For example, a bulb that was once considered the brightest may be surpassed by a newer, more efficient bulb in the future.

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