Illuminate Your Knowledge with this Bright Problem

Which light bulb will be brighter?

You have two incandescent light bulbs. One has a filament with a resistance of 20 ohm, while the second light bulb has a filament with a resistance of 40 ohm. Which light bulb will be brighter if both light bulbs are connected to identical power supplies?

Answer:

In a bulb, the power dissipated, and therefore the brightness, is inversely proportional to the resistance when connected to a constant voltage supply. Therefore, the 20 ohm bulb will be brighter.

When it comes to the brightness of light bulbs, understanding the relationship between resistance and power is key. In this scenario, where two incandescent light bulbs with different resistances are connected to the same power supply, the one with the lower resistance will shine brighter.

The power generated by a bulb is influenced by its resistance according to the formula P = V²/R, where P is power, V is voltage, and R is resistance. When two bulbs with different resistances are connected to the same power supply, the bulb with the lower resistance will draw more current and emit more power, resulting in it being brighter.

In this case, the light bulb with a resistance of 20 ohms will shine brighter than the one with 40 ohms of resistance. This is because the power dissipated in the bulb is inversely proportional to the resistance when connected to a constant voltage supply.

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