What is the solution to calculating current and power in a circuit?

AI Thread Summary
To calculate current and power in a circuit, start by identifying the potentials at key points, such as +40 mV and 0 V at the circuit's top and bottom. Introduce unknown potentials at junctions where resistors meet and compute the currents through each resistor based on these potentials. Apply Kirchhoff's current law to establish equations for the unknowns, which can then be solved to find the required values. The total power delivered by the current source can be determined once the currents are known. Clarification on the specific potentials referenced is necessary for accurate calculations.
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Homework Statement




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Homework Equations





The Attempt at a Solution



The answer is 400w and 1ma respectively, but how do I get to it?
 
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How much power does a current source deliver to a circuit? On what depends it?
Can you figure out what the potential of the various parts of the circuit is?

For part b:

1. introduce two unknown potentials for the two points where 3 resistances meet. The
potentials at the top and bottom of the circuit are +40 mv and 0.

2. compute the currents in all five resistors as a function of the 2 unknown potentials

3. use Kirchhofs current rule in the points with unknown potential from step 1 to set up 2 equations for the unknown potentials

4. solve the equations

5. compute any current needed for the answer
 
for part a should I simplify the circuit? otherwise I am still lost on how to do it

and I am even more confused by your explanation in part b, which one are you referring when you say potential at top and bottom?
 

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