How to determine the brightness of a light bulb

AI Thread Summary
The brightness of a light bulb is influenced by both current and voltage, with power being the key measure of brightness. While more current and less resistance generally lead to increased brightness, the configuration of the circuit plays a crucial role. In an ideal scenario where an incandescent bulb is 100% efficient, all power would convert to visible light, but in reality, much energy is lost as heat. Brightness can be quantified by the formula I^2R, indicating that reducing resistance while increasing current enhances brightness. Ultimately, the relationship between current, voltage, and resistance determines the overall brightness of the bulb.
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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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Both the current and voltage contributes to the brightness. It just depends on the configuration. If an incandescent is 100% efficient (with it isn't btw), that means all power (V*I) would be used to produce visible light rather than 90% being wasted as heat.
 
"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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