2/23/2022 Open Book: Problem #1: Considering Figure 3.39 in textbook (see blackboard) calculate Cob and Csb using the following data for Vos = 1.0 V and Vs8 = 0.5 V. Calculate overlap capacitances between gate and source. = = N
o* = 1x1020 cm3 Na (Substrate) = 5x1018 cm3 NA (channel stop) = 1x1020 cm? = = = LM = 65 nm Lo = 10 nm Xi = 25 nm tox = 1.5 nm Vto = 0.5 V W = 5 um 1 = 0.05, Y = 30 nm Problem #2: Using device parameters of problem # 1, Using Hn = 300 cm?/V-s calculate the drain current for VGs = 1.2 V and Vos = 0.9 V and Vse =-1 V. = =

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?

Thermal stresses are developed in a metal when its a) initial temperature is changed b) final temperature is changed c) density is changed d) thermal deformation is prevented e) expansion is prevented f) contraction is prevented

Carbon dioxide gas expands isotherm a turbine from 1 mpa, 500 k at 200 kpa. assuming the ideal gas model and neglecting the kinetic and potential energies, determine the change in entropy, heat transfer and work for each kilogram of co2.