Electric Light Bulbs: A Reflective Analysis

If light bulbs A and B consume the same power but bulb A has a resistance four times that of bulb B, what can be said about their brightness? Answer: Both bulbs have the same brightness

When comparing two light bulbs, A and B, with the same power consumption but different resistances, the question arises regarding their brightness. The data provided indicates that bulb A has a resistance four times that of bulb B. So, what implications does this have for their brightness?

The answer reveals that both bulbs have the same brightness. This conclusion can be derived from the relationship between power and brightness in electric light bulbs.

Understanding the Relationship Between Power, Resistance, and Brightness

In an electric circuit, the power consumed by a light bulb is directly related to its brightness. The formula for power in an electric circuit is given by:

P = I^2R

Where: P = Power, I = Current flowing through the circuit, and R = Resistance of the bulb.

Given that the power consumption of bulbs A and B is the same, we can establish:

Power A = Power B

Since power directly impacts brightness, it follows that:

Brightness A = Brightness B

While the resistance difference between the two bulbs affects the current passing through them, it does not alter their brightness. The increased resistance in bulb A compared to bulb B results in a lower current flowing through bulb A due to Ohm's Law (V = IR).

Therefore, despite the resistance disparity, the brightness of both bulbs remains the same. The resistance of the bulb plays a crucial role in regulating current, but it is the power consumption that ultimately determines the brightness of an electric light bulb.

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