Multiple choice Current through Bulb A

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Mdhiggenz
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Homework Statement



Circuit schematic with a battery labelled emf and a 3 A arrow on the top wire. Bulb A sits on the middle branch; bulbs B and C sit on the bottom branch. Multiple choice answer options A to D are listed, with a red check mark beside C. 2A.


Homework Equations





The Attempt at a Solution



First I originally tried using kichhoff's rules, but didn't get far.

What is throwing me off is they are giving me the current of the battery instead of the voltage. Since I know circuits in parallels all have the same voltage, I don't really know what to do.
 
Are you familiar with a current divider? Which path do you think allows more current--through A or through B-C?
 
the path through A allows for current, since the path through B-C gets split up into two small currents.
 
Both paths allow for current. Path A allows for more current because it has less resistance. Knowing this you can solve the multiple choice question by process of elimination.

Knowing what a current divider is and how to use is helpful: http://physics.eou.edu/courses/phys_223/sg2/node6.html

If you want to solve another way, find the equivalent resistance [edit-- oops no resistance specified. So assume 1Ω per bulb. You will get a resulting voltage], then find the voltage, then find the individual currents. All three of these paths lead to the same answer.
 
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