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Compute the humidity ratio of air considering the
density at 35 °C and 101 kPa is 1.05 kg/m3.
A. 0.036 kgvapor /kgair
B. 0.064 kgvapor /kgair
C. 0.36 kgvapor /kgair 1.08
D. 0.63 kgvapor /kgair
Correction!
,If atmospheric air 14.7 psia and 60 °F at sea level,
what is the pressure at 12000 ft altitude if air is
incompressible. Note: @ 60 °F: the density of air is
0.0763 lbm/ft3; P1 = 14.7 psia.
A. 5.467 psia compressible
B. 9.53 psia
C. 8.342 psia Formula:
D. 2.346 psia h1 - h 2
P2 = P1 e RT
Correction!
,A cylindrical 1 ft diameter, 4 ft high tank contains 3 ft
of water. What rotational speed is required to spin
water out of top?
A. 22.7 rad/s
B. 32.5 rad/s
C. 22.7 rad/s
D. 34.5 rad/s
Formula:
ω 2 r2
h=
g
, A two-pass surface condenser is to be designed using overall heat
transfer coefficient of 480 Btu/°F-ft2 of outside tube surface. The
tubes are to be 1 inch outside diameter with 1/16 in walls (or 7/8
in. inside diameter). Entering circulating water velocity is to be 6
ft/s. steam enters the condenser at a rate of 100,000 lb/hr at a
pressure of one psia and an enthalpy of 1090 Btu/lb. Condensate
leaves at saturated liquid at one psia. Circulating water enters the
condenser at 85 deg. F and leaves at 95 deg F. Note: 1 psia
condensate has temperature of 101.7 deg. F. Wet steam entering
becomes condensate at 101.7 deg. F with hf = 69.72 Btu/lb.
Calculate the number of tubes to be used in each pass.
A. 18, 200 tubes
B. 15, 400 tubes
C. 10, 450 tubes
D. 11, 456 tubes
Compute the humidity ratio of air considering the
density at 35 °C and 101 kPa is 1.05 kg/m3.
A. 0.036 kgvapor /kgair
B. 0.064 kgvapor /kgair
C. 0.36 kgvapor /kgair 1.08
D. 0.63 kgvapor /kgair
Correction!
,If atmospheric air 14.7 psia and 60 °F at sea level,
what is the pressure at 12000 ft altitude if air is
incompressible. Note: @ 60 °F: the density of air is
0.0763 lbm/ft3; P1 = 14.7 psia.
A. 5.467 psia compressible
B. 9.53 psia
C. 8.342 psia Formula:
D. 2.346 psia h1 - h 2
P2 = P1 e RT
Correction!
,A cylindrical 1 ft diameter, 4 ft high tank contains 3 ft
of water. What rotational speed is required to spin
water out of top?
A. 22.7 rad/s
B. 32.5 rad/s
C. 22.7 rad/s
D. 34.5 rad/s
Formula:
ω 2 r2
h=
g
, A two-pass surface condenser is to be designed using overall heat
transfer coefficient of 480 Btu/°F-ft2 of outside tube surface. The
tubes are to be 1 inch outside diameter with 1/16 in walls (or 7/8
in. inside diameter). Entering circulating water velocity is to be 6
ft/s. steam enters the condenser at a rate of 100,000 lb/hr at a
pressure of one psia and an enthalpy of 1090 Btu/lb. Condensate
leaves at saturated liquid at one psia. Circulating water enters the
condenser at 85 deg. F and leaves at 95 deg F. Note: 1 psia
condensate has temperature of 101.7 deg. F. Wet steam entering
becomes condensate at 101.7 deg. F with hf = 69.72 Btu/lb.
Calculate the number of tubes to be used in each pass.
A. 18, 200 tubes
B. 15, 400 tubes
C. 10, 450 tubes
D. 11, 456 tubes
