C. Remember that the concentration of free electrons in a metal with atomic mass A, density d Ndv and valence v (number of free electrons per atom) is given by the relation n = where N is the Avogadro's constant. i. We consider an aluminum wire (A = 27), density d = 2.7 g. cm3, resistivity 3.44 u.cm. Calculate the concentration of free electrons (number per m³). ii. Determine the mobility u of free electrons in the international system. D. For each question choose the exact answer(s). i- In an intrinsic semiconductor, the number of free electrons is: a- Equal to the number of holes b- Greater than the number of holes c- Smaller than the number of holes d- None of the previous cases is just. ii- a- An avalanche effect appears if the applied voltage exceeds a certain threshold b- A current of some micro-amps circulates despite everything in the diode c- It dissipates a strong heat iii- When a diode is polarized in the opposite direction: A full-wave rectifier circuit using a tap-off transformer requires: a- Four diodes b- One zener diode c- Two diodes iv- a- Clipping signals b- Full-wave recovery c- Voltage regulation " A One of the main applications of zener diodes is:

C. Remember that the concentration of free electrons in a metal with atomic mass A, density d Ndv and valence v (number of free electrons per atom) is given by the relation n = where N is the Avogadro's constant. i. We consider an aluminum wire (A = 27), density d = 2.7 g. cm3, resistivity 3.44 u.cm. Calculate the concentration of free electrons (number per m³). ii. Determine the mobility u of free electrons in the international system. D. For each question choose the exact answer(s). i- In an intrinsic semiconductor, the number of free electrons is: a- Equal to the number of holes b- Greater than the number of holes c- Smaller than the number of holes d- None of the previous cases is just. ii- a- An avalanche effect appears if the applied voltage exceeds a certain threshold b- A current of some micro-amps circulates despite everything in the diode c- It dissipates a strong heat iii- When a diode is polarized in the opposite direction: A full-wave rectifier circuit using a tap-off transformer requires: a- Four diodes b- One zener diode c- Two diodes iv- a- Clipping signals b- Full-wave recovery c- Voltage regulation " A One of the main applications of zener diodes is:

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter12: Electronic Control Devices

Section: Chapter Questions

Problem 14RQ

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