An ideal photovoltaic cell absorbs light using a semiconductor with a bandgap equal to 1.5 eV in an AM 1.5, global tilt spectrum. (Note that in at least some of the tables one can download, the interval between wavelengths is not always a constant throughout the spectrum. Using a trapezoidal rule in a spreadsheet or the trapz function in matlab can easily take care of this.) Assume that any photon with energy greater than the bandgap is absorbed and contributes to the short circuit current. Find the short circuit current. Find the reverse saturation current using the Cuott's fit given in class, i. e. J_0 = 2.8 times 10^-11 T^3 e^BE_g/kT_e^-Eg/kT mA/cm2 where B = 0.504. Find the maximum power this cell could provide Find the maximum theoretical efficiency of the device.

A3-mm-thick panel of aluminum alloy (k 177 w/m-k, c 875 j/kg-k and ? = 2770 kg/m) is finished on both sides with an epoxy coating that must be cured at or above t,-150°c for at least 5 min. the production line for the curing operation involves two steps: (1) heating in a large oven with air at ts,0-175°c and a convection coefficient of h, 40 w/m2. k, and (2) cooling in a large chamber with air at 25°c and a con- vection coefficient of he 10 w/m2.k. the heating portion of the process is conducted over a time interval te which exceeds the ime required to reach 150°c by 5 min (h = r + 300 s). the coating has an emissivity of ? = 0.8, and the temperatures of the oven and chamber walls are 175 and 25°c, respectively. if the panel is placed in the oven at an initial temperature of 25°c and removed from the chamber at a safe-to-touch tempera ture of 37°c, what is the total elapsed time for the two-step curing operation?