(1) Where P (watts) is the radiated power from a body of area A (m2) at temperature T (K). Îµ is emissivity, a dimensionless number between 0 and 1 that determines the. efficiency of a body to radiate and absorb energy. A perfect radiator and absorber has an emissivity of 1. Soil, ice, rock, asphalt and human skin have emissivities slightly less than 1. Ï -8is the Stefan-Boltzmann constant, 5.67 x10 Wm-2T-4 T is the body temperature in Kelvin. So if absolute temperature (in Kelvin degrees) doubles, radiated power increases by a factor of sixteen. Also, changes in temperature alter radiation peak wavelengths. Temperature increases move peak radiation to smaller wavelengths and vice-versa. Equilibrium and Solid Angles
Martin Luther King was often seen wearing a gold Rolex DayDate at many of his speaking functions. Musician John Mayer is seen here wearing his Rolex Daytona. Talk show host Ellen DeGeneres also wears a Rolex Daytona. Actor Brad Pitt is often seen wearing a Rolex Explorer.
Portia de Rossi and Ellen DeGeneres. One of Americaâs most famous lesbian âmarriagesâ could be in serious trouble, as reports indicate actress Portia de Rossi secretly filmed her âwife,â Ellen DeGeneres, to expose the TV talk-show hostâs allegedly abusive behavior. âPortia secretly taped some of their arguments,â a source told InTouch Weekly. âShe was drunk. Then she threatened to expose Ellen as controlling and manipulating.â. The source claimed DeGeneres âflew into a rageâ when she found out her partner had been recording her. The 56-year-old star of âEllenâ reportedly then combed through de Rossiâs emails to make sure she hadnât sent the videos to anyone.