A body of area 0.020m2 and emissivity 0.60 radiates power P at 800 K. Its temperature is then raised by 10 % and, simultaneously, its emissivity decreases to 0.50. What is the new power emitted per unit area expressed as a multiple of P?
a) 1.46P
b) 0.92P
c) 1.22P
d) 1.76P