[PHYS] Example Question: The cost of energy delivered to residences by electrical transmission varies from $0.070/kWh to $0.258/kWh throughout the United States; $0.110/kWh is the average value.

Example Question

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# Question

The cost of energy delivered to residences by electrical transmission varies from $0.070/kWh to $0.258/kWh throughout the United States; $0.110/kWh is the average value.

(a) At this average price, calculate the cost of leaving a 40-W porch light on for two weeks while you are on vacation?

(b) At this average price, calculate the cost of making a piece of dark toast in 3.00 min with a 915-W toaster?

(c) At this average price, calculate the cost of drying a load of clothes in 40.0 min in a 5.60 * 10^3W dryer?

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# Explanation

(a) At this average price, calculate the cost of leaving a 40-W porch light on for two weeks while you are on vacation?

 

(b) At this average price, calculate the cost of making a piece of dark toast in 3.00 min with a 915-W toaster?

 

(c) At this average price, calculate the cost of drying a load of clothes in 40.0 min in a 5.60 * 10^3W dryer?

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