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A flashlight operates on a 9.00 v battery and has a resistance of 45. At what rate does the flashlight use electric energy

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What is required is calculation of power. Power is the rate of use of energy in J/s (W).

P = VI, but V =IR => I = V/R

Then,
P = V^2/R

Where
P = Power in J/s or W
V = Voltage, in volts
R = Resistance in ohms

Substituting;
P = 9^2/45 = 1.8 W
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