Engineering, 19.11.2019 06:31 mxlx27
An led, light emitting diode, is basically just a pn junction emitting light, due to photon generation from e-h recombination, when forward biased. ideally we want current injection to be of only one type of carrier. given a gaas pn junction at t = 300k with: area = 0.7 mm2, na = 2e16 cm-3, nd = 3e17 cm-3, τn = 1e-8 sec, τp = 1e-7 sec, dn = 30 cm2/s, dp= 15 cm2/s.(a) show that the minority hole current can be ignored compared to the minority electron current.(b) when forward biased at v,-1 v, what is the photon generation rate (# photons / sec)? what is the light emission power (power-energy /time)? assume that all electrons injected into the p region recombine with holes to generate photons, i. e. quantum efficiency-1.
Answers: 3
Engineering, 03.07.2019 14:10, makaylashrout77
Amass of 1.5 kg of air at 120 kpa and 24°c is contained in a gas-tight, frictionless piston-cylinder device. the air is now compressed to a final pressure of 720 kpa. during the process, heat is transferred from the air such that the temperature inside the cylinder remains constant. calculate the boundary work input during this process.
Answers: 2
Engineering, 03.07.2019 14:10, bryneosburn
Line joining liquid phase with liquid and solid phase mixture is known as: a) liquidus b) solidus c) tie line d) none of the mentioned
Answers: 2
Engineering, 03.07.2019 15:10, margaret1758
If you were designing a bumper for a car, would you prefer it to exhibit elastic or plastic deformation? why? consider the functions of a bumper in both a minor "fender-bender" and a major collision.
Answers: 1
Engineering, 04.07.2019 18:10, settasav9641
Abrake has a normal braking torque of 2.8 kip in and heat-dissipating cast-iron surfaces whose mass is 40 lbm. suppose a load is brought to rest in 8.0 s from an initial angular speed of 1600 rev/min using the normal braking torque; estimate the temperature rise of the heat dissipating surfaces.
Answers: 3
An led, light emitting diode, is basically just a pn junction emitting light, due to photon generati...
Mathematics, 09.01.2021 06:10
Mathematics, 09.01.2021 06:10
Mathematics, 09.01.2021 06:10
Mathematics, 09.01.2021 06:10
Mathematics, 09.01.2021 06:10