Calculating power in a circuit with loops

[lagwagon555]

Homework Statement

http://img33.imageshack.us/img33/1147/question1x.jpg

Homework Equations

V = IR, Sum of currents at junction = 0.

The Attempt at a Solution

Just doing some exam revision, and found this one in my notes. I'm not really sure how to go about it. Using Kirchhoffs rules, you obviously end up with three variables, and can't solve the equations:

10 - 10I(1) - 20I(2) = 0
15 - 20I(2) - 10I(3) = 0

So I don't know how to calculate the current for any loop on the circuit, since they all have two components. Anyone got any pointers? Thanks!

 

[rl.bhat]

Take I(2) = I(1) + I(3) and solve the equations.

 

[kerimek]

I would approach this problem by first identifying the specific type of circuit that is being described. It appears to be a series-parallel circuit, with two loops. Next, I would use Ohm's Law (V=IR) to calculate the current in each individual resistor. From there, I would use Kirchhoff's Laws to analyze the circuit and determine the total current in each loop. This can be done by setting up a system of equations using the given values and the relationships between voltage, current, and resistance.

Once the total current in each loop is determined, the power in each loop can be calculated using the equation P=IV. This will give the power consumed by each resistor in the loop. To calculate the total power in the circuit, the individual powers in each loop can be added together.

In summary, the key to solving this problem is to first identify the type of circuit and then use the appropriate equations and laws to analyze it. It may also be helpful to draw a schematic diagram of the circuit to visualize the different components and their relationships.