An immersion heater used to boil water for a single cup of tea plugs into a 120 V outlet and is rated at 500 W . Suppose your super-size, super-insulated tea mug contains 400 g of water at a temperature of 18 ∘C. You can ignore the energy needed to raise the temperature of the mug and the heater itself. What is the resistance of the heater? How long will this heater take to bring the water to a boil?

An immersion heater used to boil water for a single cup of tea plugs into a 120 V outlet and is rated at 500 W . Suppose your super-size, super-insulated tea mug contains 400 g of water at a temperature of 18 ∘C. You can ignore the energy needed to raise the temperature of the mug and the heater itself. What is the resistance of the heater? How long will this heater take to bring the water to a boil?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter28: Current And Resistance

Section: Chapter Questions

Problem 57PQ

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