A 2-m2 electric heater is used to heat the air above it. The surface of the heater is at 300°C while the surrounding air is at 40°C. The heater draws 240 V and 22 A and the heat transfer coefficient is 10 W/(m2K).a) What is the rate of heat transfer into the surrounding air in Watts? b) What is the energy conversion efficiency as a percentage (a number between 0 and 100)? Report your answer to one decimal place using rounding.

A 2-m2 electric heater is used to heat the air above it. The surface of the heater is at 300°C while the surrounding air is at 40°C. The heater draws 240 V and 22 A and the heat transfer coefficient is 10 W/(m2K).a) What is the rate of heat transfer into the surrounding air in Watts? b) What is the energy conversion efficiency as a percentage (a number between 0 and 100)? Report your answer to one decimal place using rounding.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.62P

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