# Op Amp Power Accounting

An inverting amplifier circuit is constructed using a single 1-volt DC battery, three $$1\Omega$$ resistors, and one operational amplifier (op amp), as shown above.

This particular op amp is ideal, which means that it has the following properties:

• The voltages at the $$(+)$$ and $$(-)$$ terminals are identical.
• The currents (into/out of) the $$(+)$$ and $$(-)$$ terminals are zero.

Given as a percentage, to one decimal place, how much of the total power consumed by the three resistors is supplied by the 1-volt battery?

Bonus: Where does the rest of the power come from? Why is it called an inverting amplifier?

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