# Heat transfer stefan-Boltzmann

1. Aug 16, 2012

### livstudent

1. The problem statement, all variables and given/known data

Determine the temperature of the filament of a 60watt lamp, if the filament has an area of 10mm^2 and an absorptivity of 0.35. Assume stefan-Boltzmann constant is 5.67*10^-8 W/(m.K^4).

2. Relevant equations

3. The attempt at a solution

The equation I have attempted with is

Q= εσAT^4

60= 0.35*(5.67*10^-8)*(0.00001m^2)*(T^4)

T^4= 60/(0.35* 5.67*10^-8* 0.00001)

then 4th root of answer = 4169.894

is this correct?

2. Aug 16, 2012

### LawrenceC

Looks correct with the following comments:

Your answer has too many significant figures.
Your units for the Stefan-Boltzmann constant are wrong.

3. Aug 16, 2012

### livstudent

Thats what I have been given on my question sheet, also they just give numerical answers and on the sheet it says the correct answer is 3800K that is why i put it up to check??

4. Aug 17, 2012

### LawrenceC

I compute the same answer as you did.