(a) for three p-n junction diode samples a, b, and c, acceptor and donor carrier concentrations are the same 1015/cm3 and 1018 /cm3, respectively. band gaps for the three samples a, b, and c are 0.6 ev, 1.4 ev, and 1.9 ev, while the electron and hole effective masses of density of states are the same in all the three materials, me = 0.05m0 and mh = 0.2m0, where is the electron mass in free space. find the built-in potentials for these three devices at t = 300 k. comment on the comparison of estimated built-in potentials.

Antireflective coatings on solar cells are often made by applying a thin film of silicon nitride (sinx), which has an index of refractive of 1.2, on the top of the silicon solar cell, which has a refractive index of about 3.5. however, the sun emits radiation of various wavelengths which the solar cell absorbs, and the antireflective coating can only absolutely minimize the reflection of one of these wavelengths. the coating thickness is chosen to reduce the reflection of green/yellow light (e = 2.2 ev), which is the most intense color in the solar spectrum (shown below). which of the following coatings would minimize reflection of green/yellow light? the answer is 820 nm how? what is the angular width of the central maximum of an electron traveling at 2 x 108 m/s going through a single slit of width 1 mm.

Anika asks eva to roll a basketball and then a bowling ball to her. which requires more force to roll, and why?

Abeam of light shining from water to air strikes the surface at an angle greater than 48 degrees and produces total internal reflection. if the incident beam is at a 50 degree angle what angle is the reflected beam 13 25 50 100