kaplan q bank question on series circuit

[murdoc9]

here's the question:
Two light bulbs, one 60 watt bulb (higher resistance) and one 100 watt bulb (lower resistance) are placed in series. A current is run through them. Which bulb glows brighter?

and the answer:
60 watt bulb

and the explanation:
This is a paradox. You would think that the 100 watt bulb would light, but you have to reason out what is going on. A 60 watt bulb has greater resistance and when plugged in alone with the same current glows dimmer. A 100 watt bulb with less resistance draws more current and glows brighter by itself. But in series, the bulb with more resistance would draw more current, thus gets more voltage, so the 60 watt bulb glows brighter, has more power.

B is incorrect because it has lower resistance and thus lower power in series.

C is incorrect because the 60 watt bulb is drawing more current.

D is incorrect because current is distributed by the resistances of each bulb.


>>my problem is how they say "the bulb with more resistance would draw more current." isnt current the same everywhere in a series circuit?

i understand that the bulb with more resistance (60w) requires more voltage to achieve said current. but i dont get why it would be brighter. help?

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[murdoc9]

ok well i think i understand it now, but i think their explanation is wrong for anyone who cares. the current is the same through each bulb, as it should be in a series circuit. now by p = iv, it's easy to see that the higher resistance bulb (which in turn requires a higher v) will have a higher p. whichever bulb uses more power is brighter, im assuming.

im talking to myself.

 

[side effect]

glad I could help.