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Monochromatic X-rays of wavelength 1A° incident on a crystal and are
diffracted. The glancing angles for (100), (110) and (111) planes were found to
be 16.13°, 23.13° and 28.76°. Identify the crystal structure and find its lattice
constant. Hence, find the atomic weight of crystal, given the density is 8.96 g/cc
Metallic iron changes from BCC to FCC form at 9100C. At this temperature,
the atomic radii of the iron atom in the two structures are 0.1258 nm and
0.1292 nm respectively. Calculate the volume change in percentage during
this structural change. Also, calculate the percentage change in density.
Fermi Problem
If we could convert all the weight that dieters lose in the United States every year to
energy, how many gallons of gasoline would be its equivalent?
There are received 68,000 kg/h of steam by an ideal regenerative engine, having only one heater, of which the heater receives 15,400 kg/h; the condenser receives the re- mainder at 0.007 MPa. If the heater pressure is 0.96 MPa, find the state (quality or °SH) of the steam (a) at the heater entrance and (b) at the condenser entrance
Note: Draw the P-V, T-S diagrams for all problems
13. The work required to compress a gas reversibly according to PV 1.3 =C is 68KJ. if there is no flow
determine the change in internal energy, enthalpy and heat if the gas is CO 2 .
14. Air is compressed polytropically so that the quantity PV 1.4 is constant. If 0.02 m 3 of air at atmospheric pressure of 101.3 KPA and 4C are compressed to a gage pressure of 405KPAg, determine the final temperature of air in C.
Note: Draw the P-V, T-S diagrams for all problems
4. Consider that 2 lb m of air (R = 53.342 ft-lb f /lb m -R and k= 1.4) has a decrease of internal energy of 41.16 BTU while its Fahrenheit temperature is reduced to one third of its initial temperature during a
reversible nonflow constant pressure process. Determine: a) initial and final Fahrenheit temperatures, b) heat added c) Work d) change in entropy.
5. While the pressure remains constant at 700 kPaa, the volume of a system of air changes from 0.3 m 3 to 0.58 m 3 . Determine a) ∆U (kJ), b) ∆H (kJ), c) Q (kJ), d) ∆s (kJ/K)
6. An ideal gas whose mass is 1.36 kg m , R = 204.51 J/kg m and k = 1.6667. Heat added during a reversible nonflow constant pressure change of state is 316.5 kJ . The initial temperature is 37.78 o C. Determine a) change in entropy (kJ/K), b) Work (kJ), c) ratio of expansion or V 2 /V 1.
Note: Draw the P-V, T-S diagrams for all problems
1. A reversible nonflow constant volume process increases the internal energy by 316.5 kJ for 2.268 kg m of a gas for which R = 430 J/kg m -K and k = 1.35. For the process, determine a) Work, b) heat
transferred c) change in enthalpy d) change in entropy if the initial temperature is 204.4 o C..
2. A certain ideal gas has a constant R = 38.9 ft-lf f /lb m -R with k = 1.4. a) If 3 lb m of this gas undergoes a reversible nonflow constant volume process from 120 psia,740 o F to 140 o F find P 2 , ∆U, ∆H, Q, Work. b) If the process in “a” had been steady flow find work and ∆S.
3. A group of 50 persons attended a secret meeting in a room 14 m x 10 m x 3.5 m high. The room is
completely sealed off and insulated. Each person gives off 150 kCal/hr of heat and occupies a volume
of 0.2 m 3 . The room has an initial pressure 101.3 kPaa and temperature of 16 o C. Calculate the room
temperature after 10 min. NOTE: (4.187 kJ = 1 kCal)
Metallic iron changes from BCC to FCC form at 9100C. At this temperature,
the atomic radii of the iron atom in the two structures are 0.1258 nm and
0.1292 nm respectively. Calculate the volume change in percentage during
this structural change. Also, calculate the percentage change in density.
Which means of heat exchange transfers energy through waves that induce a temperature changes when absorbed by an object?
An electric motor with a 100mm diameter pulled revolves at 100 rev./min. The motor drives a line shaft by means of a flat belt, calculate the speed of the belt in meters per second. (314m/min)
#339914 on Dec 2023