How to determine the brightness of a light bulb


by cy19861126
Tags: brightness, bulb, determine, light
cy19861126
cy19861126 is offline
#1
Feb25-07, 03:00 PM
P: 69
In general, does more current/less resistence mean the brighter of the light bulb? How does voltage take into account in this case
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ranger
ranger is offline
#2
Feb25-07, 04:17 PM
PF Gold
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P: 1,686
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.
turdferguson
turdferguson is offline
#3
Feb25-07, 05:04 PM
P: 312
"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


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