A0.45 um thick sample of gaas is illuminated by a monochromatic light of photon energy 3 ev. the incident power on the sample is 15 mw/cm2. if the absorption coefficient is 50 000/cm, determine (a) the total energy absorbed by the sample per second, (b) the rate of excess thermal energy given up by the electrons to the lattice before recombination, and (c) the number of photons given off from recombination. assume perfect quantum efficiency. the outgoing radiation is of 2.35 ev.

During spring semester at mit, residents of the parallel buildings of the east campus dorms battle one another with large catapults that are made with surgical hose mounted on a window frame. a balloon filled with dyed water is placed in a pouch attached to the hose, which is then stretched through the width of the room. assume that the stretching of the hose obeys hooke's law with a spring constant of 89.0 n/m. if the hose is stretched by 5.80 m and then released, how much work does the force from the hose do on the balloon in the pouch by the time the hose reaches its relaxed length? unitst 3 number-1497 the tolerance is +/-5% open show work click if you would like to show work for this question: