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Older freezers developed a coating of ice inside that had to be melted periodically; an electric heater could speed this defrosting process. Suppose you’re melting ice from your freezer using a heating wire that carries a current of 5.0 A when connected to 120 V.
a. What is the resistance of the wire?
b. How long will it take the heater to melt 720 g of accumulated ice at –10°C? Assume that all of the heat goes into warming and melting the ice, and that the melt water runs out and doesn’t warm further.
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Chapter 22 Solutions
College Physics: A Strategic Approach Technology Update, Books a la Carte Plus Mastering Physics with Pearson eText -- Access Card Package (3rd Edition)
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