How much money will a homeowner owe an electric company if he turns on a 100.00-W incandescent light bulb and leaves it on for an entire year? (Assume that the cost of electricity is Php12.00/kWh and that the light bulb lasts that long.) The same amount of light can be provided by a 26.000-W compact fluorescent light bulb. What would it cost the homeowner to leave one of those on for a year?

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A physics student has a single-occupancy dorm room. The student has a small refrigerator that runs with a current 2 A, a lamp that contains a 100-W bulb, an overhead light with a 60-W bulb, and various other small devices adding up to 7 W. All the appliances run on a voltage of 110 V. Overall Hint a. What is the total power used by the dorm room (while the refrigerator runs)? Total power used by the dorm room is b. Assuming that the power plant for the electricity is 16 km away and uses 000-gauge copper wire (diameter 10.405 mm), how much power is dissipated in transmission (remember to count the return wire), if the power plant is directly providing the 110-V? (To be more precise, the power plant is providing the voltage it needs to provide, so that the voltage at the dorm room is 110 V.) Hint for part (b) Power of W is dissipated in transmission at 110 V. c. The most common way to increase the efficiency of power transmission is by using higher voltage for long-distance transmission…

A 12 volt car battery is being used to power a circuit with a total resistance of 0.5 Mega-ohm. a) What is the power (in watts) being used by this circuit? b) The circuit is switched on for exactly 27.3 days and then switched off. How much energy has the circuit used (in joules AND kilowatt-hours) in this time? c) If the current rate of hydro use is 10.1 cents per kilowatt-hour, how much would the use of this circuit contribute to your hydro bill (assuming that no other charges apply)?