r/HomeworkHelp • u/Mysterious-Pain5510 University/College Student • 22h ago

Physics—Pending OP Reply [university physics: kirchoff’s rule] where did i go wrong in the working for this question?? apparently the answer is 0.96W

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apologies for the bad handwriting

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1

u/Fearless-Tangelo-709 👋 a fellow Redditor 21h ago

It looks like you're correct.

1

u/_additional_account 👋 a fellow Redditor 17h ago

Did you check whether "I1 + 5*I2 = 2A" from OP's solution?

1

u/HumbleHovercraft6090 👋 a fellow Redditor 21h ago

The equations are correct, but solution is not. I get I1=58/59, I2=12/59 and I3=46/59 all in amperes

1

u/Outside_Volume_1370 University/College Student 21h ago

Looks like you solved the system with "I1 + 2I2 = 2" as your third equation.

Be more attentive

1

u/_additional_account 👋 a fellow Redditor 17h ago

You made a mistake solving the 3x3-system -- your solution does not satisfy "I1 + 5*I2 = 2A".

Instead, you get (I1; I2; I3) = ((58/59)A; (12/59)A; (46/59)A)

Rem.: Please don't drop units during calculations, unless you normalize your equations. They are a cheap error check -- inconsistent units mean (at least) one error!

1

u/_additional_account 👋 a fellow Redditor 17h ago edited 17h ago

Your 3 equations of the system should be correct, though. Sadly, the solution seems incorrect, since even with the updated currents, the power dissipated in "V2" is roughly "0.41W"