A small electric immersion heater is used to heat 84 g of water for a cup of instant coffee. The heater is labeled "81 watts" (it converts electrical energy to thermal energy at this rate). Calculate the time required to bring all this water from 21°C to 100°C, ignoring any heat losses. (The specific heat of water is 4186 J/kg-K.) Number Units

A small electric immersion heater is used to heat 84 g of water for a cup of instant coffee. The heater is labeled "81 watts" (it converts electrical energy to thermal energy at this rate). Calculate the time required to bring all this water from 21°C to 100°C, ignoring any heat losses. (The specific heat of water is 4186 J/kg-K.) Number Units

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter1: Temperature And Heat

Section: Chapter Questions

Problem 121AP: An infrared heater for a sauna has a surface area of 0.050 m2 and an emissivity of 0.84. What...

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An infrared heater for a sauna has a surface area of 0.050 m2 and an emissivity of 0.84. What temperature must it run at if the required power is 360 W? Neglect the temperature of the environment.
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