Power in an Electric HeaterAn electric heater is constructed by applying a potential difference of 120 V across a Nichrome wire that has a total resistance of 7.75 2. Find the current carried by the wire and the power rating ofthe heater.SOLUTIONConceptualize As discussed in the example The Resistance of a Nichrome Wire, Nichrome wire has high resistivity and is often used for heating elements in toasters, irons, and electric heaters.Therefore, we expect the power delivered to the wire to be relatively ---Select--- 0Categorize We evaluate the power from P = 1²R = AD-(AN²so we categorize this example as%3D---Select---problem.Analyze Use this equation to find the current (in A) in the wire:AVI =R.AFind the power rating (in kW) using the expression P1?R:P = 1?R =kWEXERCISEConsider a heater rated at 120 V with power 2.8 kW.Hint(a) What is the resistance of the heater (in 0), and the current (in A) when it is under normal operation?R =ΩI =A(b) If we connect it a 240 V source, assuming that it still works, what will be the actual power consumption now (in kW)?kW

Power in an Electric Heater An electric heater is constructed by applying a potential difference of 120 V across a Nichrome wire that has a total resistance of 7.75 Q. Find the current carried by the wire and the power rating the heater. SOLUTION Conceptualize As discussed in the example The Resistance of a Nichrome Wire, Nichrome wire has high resistivity and is often used for heating elements in toasters, Irons, and electric heaters. Therefore, we expect the power delivered to the wire to be relatively-Select- e Categorize We evaluate the power from P= ?R = (AV) R so we categorize this example as --Select- e problem. Analyze Use this equation to find the current (in A) in the wire: AV Find the power rating (in kW) using the expression P = 1R: P= PR= kW EXERCISE Consider a heater rated at 120 V with power 2.8 kW.

Power in an Electric Heater An electric heater is constructed by applying a potential difference of 120 V across a Nichrome wire that has a total resistance of 7.75 Q. Find the current carried by the wire and the power rating the heater. SOLUTION Conceptualize As discussed in the example The Resistance of a Nichrome Wire, Nichrome wire has high resistivity and is often used for heating elements in toasters, Irons, and electric heaters. Therefore, we expect the power delivered to the wire to be relatively-Select- e Categorize We evaluate the power from P= ?R = (AV) R so we categorize this example as --Select- e problem. Analyze Use this equation to find the current (in A) in the wire: AV Find the power rating (in kW) using the expression P = 1R: P= PR= kW EXERCISE Consider a heater rated at 120 V with power 2.8 kW.

Physics for Scientists and Engineers with Modern Physics

10th Edition

ISBN:9781337553292

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter26: Current And Resistance

Section: Chapter Questions

Problem 38AP

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Similar questions

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