Description : The ratio of two specific heats of air is equal to (a) 0.17 (b) 0.24 (c) 0.1 (d) 1.41 (e) 2.71.
Last Answer : Answer : d
Description : Universal gas constant is defined as equal to product of the molecular weight of the gas and (a) specific heat at constant pressure (b) specific heat at constant volume (c) ratio of two specific heats (d) gas constant (e) unity.
Description : The value of specific heat at constant pressure (cp) is __________ that of at constant volume (cv). A. less than B. equal to C. more than
Last Answer : Answer: C
Description : The ratio of specific heat at constant pressure (Cp) and specific heat at constant volume (cv) is A. equal to one B. less than one C. greater than one D. none of these
Description : According to Avogadro's Hypothesis (a) the molecular weights of all the perfect gases occupy the same volume under same conditions of pressure and temperature (b) the sum of partial pressure of ... gases have two values of specific heat (e) all systems can be regarded as closed systems.
Last Answer : Answer : a
Description : The volume of a confined gas is held constant, the pressure is directly proportional to the absolute temperature. a. Charle’s Law b. Boyle’s Law c. Joule’s Law d. Specific Heat
Last Answer : Boyle’s Law
Description : From the steam table, determine the average constant pressure specific heat (c) of steam at 10 kPa and45.8 ˚C A.1.79 kJ/ kg-˚C B.10.28 kJ/ kg-˚C C.30.57 kJ/ kg-˚C D. 100.1 kJ/ kg-˚C Formula: h = c T ∆ ∆ From the steam table At 47.7 ˚C h= 2588.1 kJ/ kg At 43.8 ˚C h= 2581.1 kJ/ kg
Last Answer : 1.79 kJ/ kg-˚C
Description : The heat supplied to the gaS at constant volume is (where m = Mass of gas, cv = Specific heat at constant volume, cp = Specific heat at constant pressure, T2 – T1 = Rise in temperature, and R = Gas constant) A. mR(T2 – T1) B. mcv(T2 – T1) C. mcp(T2 – T1) D. mcp(T2 + T1)
Last Answer : Answer: B
Description : The specific heat at constant volume is A. the amount of heat required to raise the temperature of unit mass of gas through one degree, at constant pressure B. the amount of heat required to raise ... to raise the temperature of 1 kg of water through one degree D. any one of the above
Description : The amount of heat required to raise the temperature of the unit mass of gas through one degree at constant volume, is called A.specific heat at constant volume B.specific heat at constant pressure C.kilo Joule D.none of these
Last Answer : Answer: A
Description : Change in internal energy in a closed system is equal to heat transferred if the reversible process takes place at constant (a) pressure (b) temperature (c) volume (d) internal energy (e) entropy.
Last Answer : Answer : c
Description : Change in enthalpy in a closed system is equal to heat transferred if the reversible process takes place at constant (a) pressure (b) temperature (c) volume (d) internal energy (e) entropy.
Description : The specific heat of air increases with increase in (a) temperature (b) pressure (c) both pressure and temperature (d) variation of its constituents (e) air flow
Description : A unit of pressure used in high vacuum technology, which is equal to 1mmhg. a. specific heat b. isometric c. isobaric d. torr
Last Answer : torr
Description : Which law states that the specific heat of a gas remains constant at all temperatures and pressures (a) Charles’ Law (b) Joule’s Law (c) Regnault’s Law (d) Boyle’s Law (e) there is no such law.
Description : Molecular volume of any perfect gas at 600 x 103 N/m2 and 27°C will be (a) 4.17m3/kgmol (b) 400 m3/kg mol (c) 0.15 m3/kg mol (d) 41.7 m3/kg mol (e) 417m3/kgmol.
Description : Gas being heated at constant volume is undergoing the process of. a. isometric b. specific heat c. enthalpy d. isothermal
Last Answer : isometric
Description : _____ is that property of a substance which remains constant if no heat enters or leaves the substance, while it does work or alters its volume, but which increases or diminishes should a small amount of heat enter or leave. a. Entrophy b. Enthalpy c. Specific Heat d. None of the above
Last Answer : Entrophy
Description : Which of the following parameters is constant for a mole for most of the gases at a given temperature and pressure (a) enthalpy (b) volume (c) mass (d) entropy (e) specific volume.
Last Answer : Answer : b
Description : Twenty grams of ice at 0˚C melts to water at 0˚C. How much does the entropy of the 20g change in this process? a. 30.5 J/K b. 24.6 J/K c. 21.3 J/K d. 15.7 J/K
Last Answer : 24.6 J/K
Description : The gas constant (R) is equal to the __________ of two specific heats. A. sum B. difference C. product D. ratio
Description : While swimming a depth of 13m in a fresh water lake a fish emits an air bubble of volume 2 mm² atmospheric pressure is 100kpa what is the original pressure of the bubble. a. 217.17 kpa b. 119 kpa c. 326.15 kpa d. 210 kap Pabs = Pg + Patm
Last Answer : 217.17 kpa
Description : Which of the following is not the intensive property (a) pressure (b) temperature (c) density (d) heat (e) specific volume.
Description : Which of the following quantities is not the property of the system (a) pressure (b) temperature (c) specific volume (d) heat (e) density.
Description : According to kinetic theory of gases, the absolute zero temperature is attained when (a) volume of the gas is zero (b) pressure of the gas is zero (c) kinetic energy of the molecules is zero (d) specific heat of gas is zero (e) mass is zero.
Description : What is constant for a substance that is considered “incompressible”? A. Specific volume of density B. Pressure C. Temperature D. All of the above
Last Answer : Specific volume of density
Description : In a Carnot cycle, heat is transferred at (a) constant pressure (b) constant volume (c) constant temperature (d) constant enthaply (e) any one of the above.
Description : Addition of heat at constant pressure to a gas results in (a) raising its temperature (b) raising its pressure (c) raising its volume (d) raising its temperature and doing external work (e) doing external work.
Description : Change in enthalpy of a system is the heat supplied at (a) constant pressure (b) constant temperature (c) constant volume (d) constant entropy (e) N.T.P. condition.
Description : A heat exchange process in which the product of pressure and volume remains constant is known as (a) heat exchange process (b) throttling process (c) isentropic process (d) adiabatic process (e) hyperbolic process.
Last Answer : Answer : e
Description : Ten cu ft. of air at 300 psia 400°F is cooled to 140°F at constant volume. What is the final pressure? (formula: p2 = p1T2/T1) a. 0 b. 209 psia c. - 420 psia d. None of the above
Last Answer : 209 psia
Description : According to first law of thermodynamics (a) work done by a system is equal to heat transferred by the system (b) total internal energy of a system during a process remains constant ( ... , enthalpy and entropy during a process remain constant (d) total energy of a system remains constant
Description : If a gas is heated against a pressure, keeping the volume constant, then work done will be equal to (a) + v (b) – ve (c) zero (d) pressure x volume (e) any where between zero and infinity.
Description : Is the force of gravity on unit volume? a. Specific Weight b. Specific Heat c. Specific Pressure d. Specific Volume
Last Answer : Specific Weight
Description : Sum of the internal energy of a substance and the product of pressure and volume. a. Specific Heat b. Specific Gravity c. Isolated System d. Enthalpy
Last Answer : Enthalpy
Description : What predicts the approximate molar specific heat at high temperatures from the atomic weight? A. Third law of thermodynamics B. Law of Dulong and Petit C. Mollier diagram D. Pressure-enthalpy diagram
Last Answer : Law of Dulong and Petit
Description : A problem Drum ( 3 ft. diameter ; 6 ft. height ) is field with a fluid whose density is 50 lb/ft^3. Determine the total volume of the fluid. A. 42.41 ft^3 B.44.35 ft^3 C.45.63 ft^3 D.41.23 ft^3 Formula: Vf = (pi d^2 h) / 4
Last Answer : 42.41 ft^3
Description : Ten cu. ft of air at 300psia and 400°F is cooled to 140°F at constant volume. What is the transferred heat? a.-120Btu b. -220Btu c.-320Btu d. -420Btu formula: Q= mcv(T2-T1)
Last Answer : -420Btu
Description : Is a steady flow process at total constant pressure through a control volume for which there is no heat? a. Adiabatic Saturation Process b. Dew point c. Adiabatic Ratio d. None of the above
Last Answer : Adiabatic Saturation Process
Description : As we heat a gas at constant pressure, its volume a. increases b. decreases c. stays the same d. none of the above
Last Answer : increases
Description : On volume basis, air contains following parts of oxygen (a) 21 (b) 23 (c) 25 (d) 77 (e) 79.
Description : On weight basis, air contains following parts of oxygen (a) 21 (b) 23 (c) 25 (d) 73 (e) 79.
Description : According to Avogadro's law A. the product of the gas constant and the molecular mass of an ideal gas is constant B. the sum of partial pressure of the mixture of two gases is sum of the ... all gases, at the same temperature and pressure, contain equal number of molecules D. all of the above
Description : If air is at pressure, p, of 3200 lbf/ft2 , and at a temperature, T, of 800 ˚R, what is the specific volume, v? (R=5303 ft-lbf/lbm-˚R, and air can be modeled as an ideal gas.) A.9.8 ft^3/lbm B.11.2 ft^3/lbm C.13.33 ft^3/lbm D.14.2 ft^3/lbm Formula: pv = RT v = RT / p
Last Answer : 13.33 ft^3/lbm
Description : Water (specific heat cv= 4.2 kJ/ kg ∙ K ) is being heated by a 1500 W h eater. What is the rate of change in temperature of 1kg of the water? A. 0.043 K/s B. 0.179 K/s C. 0.357 K/s D. 1.50 K/s Formula: Q = mcv ( T)
Last Answer : 0.179 K/s
Description : What is the resulting pressure when one pound of air at 15 psia and 200 ˚F is heated at constant volume to 800 ˚F? A.15 psia B. 28.6 psia C. 36.4 psia. D. 52.1 psia Formula : T1/p1 = T2/p2 p2= p1T2 / T1
Last Answer : 28.6 psia
Description : _________ is the temperature to which the air must be cooled, at constant pressure, to produce saturation. a. relative humidity b. triple point temperature c. dew point d. critical point
Last Answer : dew point
Description : On a day when the partial pressure of water vapor remains constant, what happens as the temperature rises? a. the relative humidity increases b. the relative humidity decreases c. the relative humidity remains constant d. the air would eventually become saturated
Last Answer : the relative humidity decreases
Description : 3.0 lbm of air are contained at 25 psia and 100 ˚F. Given that Rair = 53.35 ft-lbf/lbm- ˚F, what is the volume of the container? A.10.7 ft^3 B.14.7 ft^3 C.15 ft^3 D.24.9 ft^3 Formula: use the ideal gas law pV = mRT T = (100 +460) ˚R V = mRT/p
Last Answer : 24.9 ft^3
Description : A simple steam engine receives steam from the boiler at 180˚C and exhausts directly into the air at 100˚C. What is the upper limit of its efficiency? a. 11.28 % b. 36.77 % c. 20.36 % d. 17.66 %
Last Answer : 17.66 %