How to Simplify and Find Power in a Circuit?

AI Thread Summary
The discussion focuses on simplifying a complex circuit and calculating the power dissipated across its resistors. The user initially attempts to simplify the circuit by combining resistors in parallel and series, arriving at an equivalent resistance of 8.8 ohms. However, further clarification reveals that the correct equivalent resistance is actually 10 ohms when considering the proper arrangement of resistors. The power dissipated in the 15-ohm resistor is calculated to be 25.35 watts, but the user seeks guidance on finding the power dissipated in the remaining resistors. The conversation emphasizes the importance of accurately identifying resistor configurations for effective circuit analysis.
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Homework Statement



[PLAIN]http://img802.imageshack.us/img802/9172/qns33.png

Simplifying the circuit?

Also find the power dissipated in the circuit?

Homework Equations


P=I^2R

V=IR

The Attempt at a Solution



I tired to simply the diagonal by making it parallel with (15+18ohms) and the (10+16ohms) and i get

R = (\frac{1}{33}+\frac{1}{48}+\frac{1}{16})^{-1} = 8.8ohms<br />
Power of 15ohms is: 1.3^2 * 15 = 25.35W

Now how would i find the power dissipated for the rest of the resistors?

P.S
 
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Paymemoney said:

Homework Statement



[PLAIN]http://img802.imageshack.us/img802/9172/qns33.png
...

I tried to simply the diagonal by making it parallel with (15+18ohms) and the (10+16ohms) and i get

R = (\frac{1}{33}+\frac{1}{48}+\frac{1}{16})^{-1} = 8.8ohms<br />

The 48 Ω resistor is in parallel with the (10 Ω + 6 Ω ) combination.

\displaystyle R_{48,10,6}=\left({{1}\over{48}} + {{1}\over{16}} \right)^{-1}\Omega = 12\ \Omega

This combination, \displaystyle R_{48,10,6}\,, is in series with the 18 Ω resistor.

The 15 Ω resistor is in parallel with the combination of the other 4 resistors.

 
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So it will end up being 10ohms when you have simplified everything.
 
Paymemoney said:
I tired to simply the diagonal by making it parallel with (15+18ohms) and the (10+16ohms) and i get

Whoa! The 15 and 18 ohm resistors have another branch coming off of their mutual junction; They won't simplify to being simply in parallel.

Now, you *could* get fancy (and complicated) and use something called a Delta-Y transformation on resistors 15, 18, and 48, but it is not necessary if you spot the fact that the 10 and 6 ohm resistors are already alone in series, so that their sum parallels the 48 ohm resistor directly.
 
Paymemoney said:
So it will end up being 10ohms when you have simplified everything.

Yes. The equivalent resistance for the circuit is 10 Ω.
 
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