The recovery time of a hot water heater is the time required to heat all the water in the unit to the desired temperature. Suppose that a 20-gallon (1.00 gal = 3.79 x 10-3 m3) unit starts with water at 14 °C and delivers hot water at 55 °C. The unit is electric and uses a resistance heater (120 V AC, 3.4 Ω) to heat the water. If water has a specific heat capacity of 4186 J/(kg°C) and a density of 1000 kg/m3, and assuming that no heat is lost to the environment, what is the recovery time of this hot water heater?

The recovery time of a hot water heater is the time required to heat all the water in the unit to the desired temperature. Suppose that a 20-gallon (1.00 gal = 3.79 x 10-3 m3) unit starts with water at 14 °C and delivers hot water at 55 °C. The unit is electric and uses a resistance heater (120 V AC, 3.4 Ω) to heat the water. If water has a specific heat capacity of 4186 J/(kg°C) and a density of 1000 kg/m3, and assuming that no heat is lost to the environment, what is the recovery time of this hot water heater?

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter17: Current And Resistance

Section: Chapter Questions

Problem 48P: An office worker uses an immersion heater to warm 250 g of water in a light, covered, insulated cup...

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