Multiple choice Current through Bulb A

[Mdhiggenz]

Homework Statement

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.

 

[lewando]

Are you familiar with a current divider? Which path do you think allows more current--through A or through B-C?

 

[Mdhiggenz]

the path through A allows for current, since the path through B-C gets split up into two small currents.

 

[lewando]

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.

 

[Nickie]

I would suggest approaching this problem by first understanding the basic principles of electricity and circuits. It is important to understand Ohm's Law, which states that voltage is equal to current multiplied by resistance (V=IR). This can help in understanding the relationship between voltage, current, and resistance in a circuit.

In this case, we are given the current through Bulb A, which means that the current is flowing through that specific part of the circuit. This can be represented by the equation I = V/R, where V is the voltage and R is the resistance of Bulb A.

Next, we can use Kirchhoff's Laws to analyze the circuit. Kirchhoff's Current Law states that the sum of all currents entering a junction must equal the sum of all currents leaving the junction. So, in this case, the current through Bulb A must be equal to the sum of the currents through Bulb B and Bulb C.

We can then use Kirchhoff's Voltage Law, which states that the sum of all voltage drops in a closed loop must equal the sum of all voltage sources in the loop. In this case, the voltage drop across Bulb A must be equal to the voltage source (the battery) in the circuit.

By applying these principles, we can solve for the voltage and resistance of Bulb A, which will give us a better understanding of the circuit and how it is functioning. It is important to approach problems like this with a clear understanding of the fundamental concepts and to use mathematical equations to help solve the problem.