Power and Cost of Electricity Problem set P=VxI, V=IxR, Q=IxT, E=Pxt,

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Power and Cost of Electricity Problem set P=VxI, V=IxR, Q=IxT, E=Pxt, E=VxQ 1. What is the potential difference across 1250W baseboard heater that draws 5.2A? 2. If 700W toaster and 1100W kettle are plugged into the same 120V outlet in parallel, what total current will they drive? 3. What is the maximum power that may be used in a circuit with a potential difference of 120V and 20A fuse? 4. A portable heater is plugged into a 120V outlet and draws a current of 8.0 A for 10 minutes. Calculate each of the following: a) the quantity of electric charge that flows through the heater b) the energy consumed by the heater c) the power dissipated by the heater 5. Find a cost of operating an electric toaster for 3.0h if it draws 5.0A from a 120V outlet. Electric energy costs 5.5cents per kWh. 6. What is the cost to a storekeeper of leaving a 40W light burning near his safe over the weekend, for 60 hours, if electricity costs 4.5cents per kWh? 7. The blower motor of an oil furnace, rated at 250W, comes on for an average of 5.0 minutes at a time, a total of 48 times a day. What is the monthly cost of operating the motor, if electricity costs 4.2cents per kWh? 8. The following appliances were operated f or a thirty day month, in a 120V circuit; a coffee percolator of resistance 15 Ω for 0.5 hours per day, a 250W electric drill for 2.0 hours/day, and a toaster that draws 5.0A for 15min/day. Calculate the electric bill for the month at an average cost of 6 cents per kW? 
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