# Physics - electricity

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An incandescent lamp is marked '120v,75W'

a)what is the current in the lamp under normal condition of operation?

b)How much does it cost per hour to operate the lamp if the price of electrical energy is \$6.00 per unit?

Please stop posting under different names.

Use ohms law, remembering Power is I*V

Cost= power*time

• Physics - electricity -

a. P = E*I = 75W
120I = 75
I = 0.625A

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