1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How to determine the brightness of a light bulb

  1. Feb 25, 2007 #1

    cy19861126

    User Avatar

    In general, does more current/less resistence mean the brighter of the light bulb? How does voltage take into account in this case
     
    cy19861126, Feb 25, 2007
  2. jcsd
    Phys.org - latest science and technology news stories on Phys.org
  3. Feb 25, 2007 #2

    ranger

    User Avatar
    Gold Member

    Both the current and voltage contributes to the brightness. It just depends on the configuration. If an incandescent is 100% efficient (with it isnt btw), that means all power (V*I) would be used to produce visible light rather than 90% being wasted as heat.
     
    ranger, Feb 25, 2007
  4. Feb 25, 2007 #3

    turdferguson

    User Avatar

    "Brightness" is a measure of power, so at constant voltage power is I^2R. If resistance is decreased and current is increased by an equal factor, the increase in current counts for more and the bulb will appear brighter
     
    turdferguson, Feb 25, 2007
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: How to determine the brightness of a light bulb

  1. What determines the brightness of bulbs? (Replies: 1)

  2. Light Bulb Brightness (Replies: 2)

  3. Light bulb brightness in a circuit (Replies: 1)

  4. Help with determining brightness of light bulbs in a circuit (Replies: 2)

  5. DC Circuits - How to Determine a Bulb's Brightness (Replies: 7)

Loading...