What Is Constant Volume System?

1 Answer

Answer :

Constant Air Volume (CAV) is a type of heating, ventilating, and air-conditioning (HVAC) system. In a simple CAV system, the supply air flow rate is constant, but the supply air temperature is varied to meet the thermal loads of a space. Most CAV systems are small, and serve a single thermal zone.

Related questions

Description : Gas is enclosed in a cylinder with a weighted piston as the stop boundary. The gas is heated and expands from a volume of 0.04 m^3 to 0.10 m^3 at a constant pressure of 200kPa.Calculate the work done by the system.  A. 8 kJ  B. 10 kJ  C.12 kJ  D.14 kJ Formula: W = p(V2-V1)

Last Answer : 12 kJ

Description : Twenty grams of oxygen gas are compressed at a constant temperature of 30 ˚C to 5%of their original volume. What work is done on the system.  A.824 cal  B.924 cal  C.944 cal  D.1124 cal Formula: W = -mRTln (V2/V1) Where R = (1.98 cal/gmole·K) (32 g/gmole)

Last Answer : 1124 cal

Description : A gas is enclosed in a cylinder with a weighted piston as the top boundary. The gas is heated and expands from a volume of 0.04 m3 to 0.10 m3 at a constant pressure of 200 kPa. Find the work done on the system.  a. 5 kJ  b. 15 kJ  c. 10 kJ  d. 12 kJ

Last Answer : 12 kJ

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.

Last Answer : Answer : a

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.

Last Answer : Answer : a

Description : Extensive property of a system is one whose value  (a) depends on the mass of the system like volume  (b) does not depend on the mass of the system, like temperature, pressure, etc.  (c) is not ... the state  (d) is dependent on the path followed and not on the state  (e) is always constant.

Last Answer : Answer : a

Description : Intensive property of a system is one whose value  (a) depends on the mass of the system, like volume  (b) does not depend on the mass of the system, like temperature, pressure, etc.  (c) is not ... on the state  (d) is dependent on the path followed and not on the state  (e) remains constant.

Last Answer : Answer : b

Description : Out of constant pressure and constant volume lines on TS diagram which line has higher slope ? And whether slope is constant or variable ?

Last Answer : Constant volume line. Slope is variable.

Description : What are the names given to constant temperature, constant pressure, constant volume, constant internal energy, constant enthalpy, and constant entropy processes.

Last Answer : Isothermal, isochroic, isobaric, free expression, throttling and adiabatic processes respectively.

Description : The volume of a gas under constant pressure increases or decrease with temperature.  a. Gay- Lussac’s Law  b. Ideal Gas Law  c. Charles’ Law  d. Boyle’s Law

Last Answer : Charles’ Law

Description : What Law states that the pressure of gas is inversely proportional to its volume at constant temperature?  a. Charles’ law  b. Gay-Lussac’s Law  c. Boyle’s Law  d. Dalton’s Law

Last Answer : Boyle’s Law

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 : 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 : The pressure of the confined gas is held constant, the volume directly proportional to the absolute temperature.  a. Charle’s Law  b. Boyle’s Law  c. Zeroth Law  d. Gas Law

Last Answer : Charle’s Law

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 : “If the temperature o f a fixed quantity of a gas is held constant during a change of state, the volume varies inversely with the absolute pressure.  a. Charle’s Law  b. Boyle’s Law  c. Dalton’s Law  d. Amagat’s Law

Last Answer : Boyle’s Law

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 : A gas having a volume of100 ft³ at 27ºC is expanded to 120 ft³by heated at constant pressure to what temperature has it been heated to have this new volume?  a. 87°C  b. 85°C  c. 76°C  d. 97°C t2= T2–T1

Last Answer : 87°C

Description : The volume of the gas held at constant pressure increases 4 cm² at 0°C to 5cm². What is the final pressure?  a. 68.65ºC  b. 68.25ºC  c. 70.01°C  d. 79.1ºC t2= T2–T1

Last Answer : 981 N

Description : There are 1.36 kg of gas, for which R = 377 J/kg.k and k = 1.25, that undergo a nonflow constant volume process from p1 = 551.6 kPa and t1 = 60°C to p2 = 1655 kPa. During the process the gas is internally stirred and ... (Formula: T2= T1p2/ p1)  a. 999 K  b. 888 K  c. 456 K  d. One of the above

Last Answer : 999 K

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 : 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 : An ideal gas is maintained at constant temperature. If the pressure on the gas is doubled, the volume is  a. increased fourfold  b. doubled  c. reduced by half  d. decreased by a quarter

Last Answer : reduced by half

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 : The gas in a constant gas thermometer cooled to absolute zero would have _________.  a. no volume  b. no pressure  c. zero temperature at all scales  d. none of the above

Last Answer : no pressure

Description : The volume of a given amount of water _________ as the temperature decreases from 4˚C to 0˚C.  a. decreases  b. increases  c. remains constant  d. none of the above

Last Answer : increases

Description : “At constant pressure, the volume of a gas is inversely proportional to the pressure”. This is known as ______.  A. Boyle’s Law  B. Charles’s Law  C. Gay-Lussac Law  D. Ideal gas law

Last Answer : Boyle’s Law

Description : What remains constant during a steady-flow process?  A. Mass  B. Energy content of the control volume  C. Temperature  D. Mass and energy content of the control volume

Last Answer : Mass and energy content of the control volume

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 : The mass of one mole of a substance in grams is known as ______.  A. Molar weight  B. Molar mass  C. Molar volume  D. Molar constant

Last Answer : Molar mass

Description : What is the energy absorbed during chemical reaction under constant volume conditions?  A. Entropy  B. Ion exchange  C. Enthalpy  D. Enthalpy of reaction

Last Answer : Enthalpy

Description : What gas thermometer is based on the principle that at low pressure, the temperature of a gas is proportional to its pressure at constant volume?  A. Constant-pressure gas thermometer  B. Isobaric gas thermometer  C. Isometric gas thermometer  D. Constant-volume gas thermometer

Last Answer : Constant-volume gas thermometer

Description : The temperatures of the ideal gas temperature scale are measured by using a ______.  A. Constant-volume gas thermometer  B. Constant-mass gas thermometer  C. Constant-temperature gas thermometer  D. Constant-pressure gas thermometer

Last Answer : Constant-volume gas thermometer

Description : What is a process during which the specific volume remains constant?  A. Isobaric process  B. Isothermal process  C. Isochoric or isometric process  D. Isovolumetric process

Last Answer : Isochoric or isometric process

Description : For a perfect gas, according to Boyle’s law (where p = Absolute pressure, v = Volume, and T = Absolute temperature)  A. p v = constant, if T is kept constant  B. v/T = constant, if p is kept constant  C. p/T = constant, if v is kept constant  D. T/p = constant, if v is kept constant

Last Answer : Answer: A

Description : Otto cycle is also known as  A. constant pressure cycle  B. constant volume cycle  C. constant temperature cycle  D. constant temperature and pressure cycle

Last Answer : Answer: B

Description : Otto cycle efficiency is higher than Diesel cycle efficiency for the same compression ratio and heat input because in Otto cycle  A. combustion is at constant volume  B. expansion and compression are isentropic  C. maximum temperature is higher  D. heat rejection is lower

Last Answer : Answer: D

Description : The dual combustion cycle consists of one constant pressure, two constant volume and two isentropic processes.  A. Agree  B. Disagree

Last Answer : Answer: A

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

Last Answer : Answer: B

Description : The absolute pressure of a given mass of a perfect gas varies inversely as its volume, when the temperature remains constant. This statement is known as Charles’ law.  A. Yes  B. No

Last Answer : Answer: B

Description : According to Gay-Lussac law, the absolute pressure of a given mass of a perfect gas varies __________ as its absolute temperature, when the volume remains constant.  A. directly  B. indirectly

Last Answer : Answer: A

Description : The constant pressure, constant volume and constant pvn processes are regarded as irreversible process.  A. True  B. False

Last Answer : Answer: A

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 : If the value of n = 0 in the equation pvn = C, then the process is called  A. constant volume process  B. adiabatic process  C. constant pressure process  D. isothermal process

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

Last Answer : Answer: C

Description : When the gas is heated at constant volume, the heat supplied increases the internal energy of the gas.  A.True  B.False

Last Answer : Answer: A

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