The surface of the sun has temperature of approximately 6000 ®k. in radiative heat transfer analysis, the amount of radiation from a hot surface (such as the sun) is obtained from plank's equation: e. _ 21h02 1 24.exp(ch/kt2)-1 in this equation, en is the spectral irradiance (in watts/m²-um), h=6.62608x10-34 joule-s is the plank's constant, c= 3x108 m/s is the speed of light, k= 1.38066x10-23 joules/ºk is the boltzmann constant, t is the temperature (in °k), and i is the wavelength of radiation. in the exponential term, 2 must be in meters units. in the denominator, 24 must be in mº units, and 2 must be in um units. we want to find the amount of radiation from the sun in part of the near-infrared region using 1.0–7.0 um range, by finding the integral i = so en da. it gives us the energy emitted from the sun in the selected range (in watts/m² units). (a) apply the midpoint rule to calculate the integral, using h= 1.5 um. (b) using a plotting software, draw a log-log plot of the function ea for the range a = 0.1–10.0 um, and also show the midpoint lines (similar to the drawing in fig. 5.6 of the textbook). you will notice that the maximum amount of radiation from the sun falls in the visible range (0.4-0.7 um)!