(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 40-cm-long, 0.6-cm-diameter electric resistance wire is used to determine the convection heat transfer coefficient in air at 25 degrees C experimentally. The surface temperature of the wire is measured to be 150 degrees C when the electric power consumption is 90 W. If theradiationheat loss from the wire is calculated to be 30 W, the convection heat transfer coefficient is : ?

2. Relevant equations

Q (convection) = h * A * (delta T)

h = stefan-boltzmann constant

A = surface area

3. The attempt at a solution

I set the equation equal to h and solve. I get h = 0.318 W/ M^2, which is not one of the given answers (multiple choice). Two things that confuse me :

1 .Why was I given the amount of radiation transfer when all of the other information pertains to convectrion? (I think this might be a typo, I'm going to email my instructor)

2. Why was the amount of power going through the wire ( 90 Watts ) given? Do I need this information?

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# Homework Help: Convection/(radiation ?) heat loss problem. (Thermodynamics)

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