Power in Circuits Video Lessons

Concept

# Problem: If you use an extension cord, current travels from the 120 V outlet, along one wire inside the cord, through the appliance you've plugged into the cord, and back to the outlet through a second wire in the cord. The total resistance of the two wires in a light-duty extension cord is 0.48Ω; the current through such a cord should be limited to 13 A. A 13 A shop vacuum is powered using this cord.1) What is the voltage drop across the vacuum?2) How much power does the vacuum use?3) How much power is dissipated in the cord?

###### FREE Expert Solution

Ohm's law:

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###### Problem Details

If you use an extension cord, current travels from the 120 V outlet, along one wire inside the cord, through the appliance you've plugged into the cord, and back to the outlet through a second wire in the cord. The total resistance of the two wires in a light-duty extension cord is 0.48Ω; the current through such a cord should be limited to 13 A. A 13 A shop vacuum is powered using this cord.
1) What is the voltage drop across the vacuum?
2) How much power does the vacuum use?
3) How much power is dissipated in the cord?