1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Heat radiation

  1. Jan 30, 2016 #1
    1. The problem statement, all variables and given/known data
    At what rate does a 0.1m cube of metal with emissivity e=0.75 radiate energy if it is at a temperature of 200C?

    2. Relevant equations

    H=AeσT^4, σ=5.67 x10^-8
    3. The attempt at a solution
    I found the area of the cute to be A=(0.1m)^2=0.01m, and the turned 200C into 473K, but when I type them all in I get 21.28W and the answer is 128W?
     
  2. jcsd
  3. Jan 30, 2016 #2

    gneill

    User Avatar

    Staff: Mentor

    How many faces does a cube have?
     
  4. Jan 30, 2016 #3
    6.. thanks!
     
  5. Jan 30, 2016 #4

    SteamKing

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Also, (0.1 m)2 = 0.01 m2 Don't forget to square the units.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted