Which Light Bulb Has Greater Resistance?

Two light bulbs A and B are connected in series so they carry the same current. Light bulb A is brighter than light bulb B. Which bulb has greater resistance?

1) Bulb A
2) Bulb B
3) Both bulbs have the same resistance
4) Cannot be determined

Final answer:

In a series circuit, the brighter bulb A dissipates more power and must have lower resistance than the dimmer bulb B, which converts less electrical energy into light and has higher resistance.

Explanation:

If two light bulbs, A and B, are connected in series and A is brighter than B, it implies that bulb A has lower resistance. The reason is that in a series circuit, the current flowing through each component is the same. Since bulb A is brighter, it dissipates more power, which according to the power formula P = I2R means that its resistance must be lower, so it converts more of the electrical energy into light and heat. On the other hand, bulb B, being less bright, suggests it converts less electrical energy into light, thus has a higher resistance.

Two light bulbs A and B are connected in series so they carry the same current. Light bulb A is brighter than light bulb B. Which bulb has greater resistance? In a series circuit, the brighter bulb A dissipates more power and must have lower resistance than the dimmer bulb B, which converts less electrical energy into light and has higher resistance.
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