SHRI RAMSWAROOP MEMORIAL COLLEGE OF ENGG. & MANAGEMENT

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1 B.Tech. [SEM III (ME-31, 32, 33,34,35 & 36)] QUIZ TEST-1 Time: 1 Hour THERMODYNAMICS Max. Marks: 30 (EME-303) Note: Attempt All Questions. Q1) 2 kg of an ideal gas is compressed adiabatically from pressure 100kPa and temperature 220K to a final pressure of 400kPa. Make calculation for (i)initial volume, (ii) final volume and temperature, (iii) work performed,(iv) heat interaction to or from the system, and (iv) change in internal energy. It may be presumed that for the given ideal gas C p =1kJ/kg K and C v =0.707kJ/kg K (Question-6) [5] Q2) A platinum wire is used as a resistance thermometer. The wire resistance was found to be 10 ohm and 16 ohm at ice point and steam point respectively and 30 ohm at sulphur boiling point of C,Find the resistance of wire at C if the resistance varies with temperature by the relation R=R 0 (1+αt+βt 2 ) (Question-9) [5] Q1) The heat at constant pressure of a certain system is a function of temperature only and may be expressed as C p = / (t+100) J/ 0 C Where t is the temperature of the system in 0 C.The system is heated while it is maintained at pressure of 1 atmosphere until its volume increases from 2000 cm 3 to 2400 cm 3 and its temperature increases from 0 0 C to C. (a) Find the magnitude of the heat interaction. (b) How much does the internal energy of the system. Q2) A blower handles 1 kg of air at 20 0 C and consume a power of 15kW. The inlet and outlet velocities of air are 100 m/s and 150 m/s respectively. Find the exit air temperature, assuming adiabatic condition. Take C p =1.005 kj/kg-k. Q3) In a gas turbine the gas enter at the rate of 5 kg/s with the velocities of 50 m/s and enthalpy of 900 kj/kg and leaves the turbine with a velocities of 150 m/s and enthalpy of 400 kj/kg. The loss of heat from the gases to the surrounding is 25 kj/kg. Assuming for gas R=0.287 kj/kg K and C p =1.005 kj/kg K and inlet conditions to be at 100 kpa and 27 0 C. Determine the power the output of the turbine and the diameter of the inlet pipe. EME-303/ Mr. Arun Sharma,Mr.Ajay Kr.Verma Date:

2 B.Tech. [SEM III (ME-31, 32, 33,34,35 & 36)] QUIZ TEST-1 Time: 1 Hour THERMODYNAMICS Max. Marks: 30 (EME-303) Note: Attempt All Questions. Q1). A system comprising of a gas of 5 kg mass undergoes expansion process from 1MPa and 0.5m 3 to 0.5 MPa. Expansion process is governed by p.v 1.3 = constant. The initial energy of a gas is given by, u=1.8 pv+ 85 kj/kg. Here u is specific internal energy, p is pressure in kpa, and v is specific volume in m 3 /kg Determine heat and work interaction and change in internal energy. (Question-10) [5] Q2) A completely evacuated tank fully insulated is filled with 10 kg of air passing through a charging line maintain at a pressure of 1000kPa and enthalpy of 400 kj/kg final equilibrium state in the tank is 1000 kpa. enthalpy of 600 kj/kg and specific volume of 0.17 m 3 /kg the air in the vessel is heated by heating coil. Then find the heat transfer (Question-14) [5] Q1) The heat at constant pressure of a certain system is a function of temperature only and may be expressed as C p = / (t+100) J/ 0 C Where t is the temperature of the system in 0 C.The system is heated while it is maintained at pressure of 1 atmosphere until its volume increases from 2000 cm 3 to 2400 cm 3 and its temperature increases from 0 0 C to C. (a) Find the magnitude of the heat interaction. (b) How much does the internal energy of the system. Q2) A blower handles 1 kg of air at 20 0 C and consume a power of 15kW. The inlet and outlet velocities of air are 100 m/s and 150 m/s respectively. Find the exit air temperature, assuming adiabatic condition. Take C p =1.005 kj/kg-k. Q3) In a gas turbine the gas enter at the rate of 5 kg/s with the velocities of 50 m/s and enthalpy of 900 kj/kg and leaves the turbine with a velocities of 150 m/s and enthalpy of 400 kj/kg. The loss of heat from the gases to the surrounding is 25 kj/kg. Assuming for gas R=0.287 kj/kg K and C p =1.005 kj/kg K and inlet conditions to be at 100 kpa and 27 0 C. Determine the power the output of the turbine and the diameter of the inlet pipe. EME-303/ Mr. Arun Sharma,Mr.Ajay Kr.Verma Date:

3 B.Tech. [SEM III (ME-31, 32, 33,34,35 & 36)] QUIZ TEST-1 Time: 1 Hour THERMODYNAMICS Max. Marks: 30 (EME-303) Note: Attempt All Questions. Q1) A vertical piston cylinder assembly that initially has a volume of 0.1m3 is filled with 0.1 kg of nitrogen gas. This is weighted so that the pressure of nitrogen is always maintained at 1.15 bar. Heat transfer is allowed to take place until the volume is reduced to 75% of initial volume. Determine: (i) initial and final temperatures of nitrogen (ii) magnitude and direction of heat transfer. Assume the process to be quasi static and take Cv=0.745kJ/kg K for nitrogen. (Question-11) [5] Q2) A fluid is confined in acylender by a spring loaded frictionless piston so that pressure in the fluid is linear function of volume p=a+bv internal energy of the fluid is given by U= PV where U is in kj,p in kpa and Vin m 3 if the fluid changes from initial states of P 1 =170kPa, P 2 =400kPa, V 1 =0.03m 3 and V 2 =0.06m 3. Find the direction and magnitude of heat and work transfer. (Question-12) [5] Q1) The heat at constant pressure of a certain system is a function of temperature only and may be expressed as C p = / (t+100) J/ 0 C Where t is the temperature of the system in 0 C.The system is heated while it is maintained at pressure of 1 atmosphere until its volume increases from 2000 cm 3 to 2400 cm 3 and its temperature increases from 0 0 C to C. (a) Find the magnitude of the heat interaction. (b) How much does the internal energy of the system. Q2) A blower handles 1 kg of air at 20 0 C and consume a power of 15kW. The inlet and outlet velocities of air are 100 m/s and 150 m/s respectively. Find the exit air temperature, assuming adiabatic condition. Take C p =1.005 kj/kg-k. Q3) In a gas turbine the gas enter at the rate of 5 kg/s with the velocities of 50 m/s and enthalpy of 900 kj/kg and leaves the turbine with a velocities of 150 m/s and enthalpy of 400 kj/kg. The loss of heat from the gases to the surrounding is 25 kj/kg. Assuming for gas R=0.287 kj/kg K and C p =1.005 kj/kg K and inlet conditions to be at 100 kpa and 27 0 C. Determine the power the output of the turbine and the diameter of the inlet pipe. EME-303/ Mr. Arun Sharma,Mr.Ajay Kr.Verma Date:

4 B.Tech. [SEM III (ME-31, 32, 33,34,35 & 36)] QUIZ TEST-1 Time: 1 Hour THERMODYNAMICS Max. Marks: 30 (EME-303) Note: Attempt All Questions. Q1) An insulated rigid pressure vessel divided into two poprtions by a movable partition, one part of vessel is occupied by an ideal gas at pressure P 1 volume V 1 and temperature T 1 the other part is occupied by the same ideal gas but at pressure P 2 and volume V 2 and temperature T 2. The partition is removed and the two portion is mixed adiabatically show that the final pressure and temperature is given by (Question-13) [5] P 3 = (P 1 V 1 +P 2 V 2 )/(V 1 +V 2 ) T 3 = (P 1 V 1 +P 2 V 2 )/ (P 1 V 1 /T 1 +P 2 V 2 /T 2 ) Q2) A spherical balloon of 1m diameter contains a gas at 150 kpa.gas inside the balon is heated until the pressure reaches 450 kpa, During the process of heating pressure of gas pressure of gas inside the balloon is proportional to cube of diameter of balloon. Find the work done by the gas inside the balloon. (Question-4) [5] Q1) The heat at constant pressure of a certain system is a function of temperature only and may be expressed as C p = / (t+100) J/ 0 C Where t is the temperature of the system in 0 C.The system is heated while it is maintained at pressure of 1 atmosphere until its volume increases from 2000 cm 3 to 2400 cm 3 and its temperature increases from 0 0 C to C. (a) Find the magnitude of the heat interaction. (b) How much does the internal energy of the system. Q2) A blower handles 1 kg of air at 20 0 C and consume a power of 15kW. The inlet and outlet velocities of air are 100 m/s and 150 m/s respectively. Find the exit air temperature, assuming adiabatic condition. Take C p =1.005 kj/kg-k. Q3) In a gas turbine the gas enter at the rate of 5 kg/s with the velocities of 50 m/s and enthalpy of 900 kj/kg and leaves the turbine with a velocities of 150 m/s and enthalpy of 400 kj/kg. The loss of heat from the gases to the surrounding is 25 kj/kg. Assuming for gas R=0.287 kj/kg K and C p =1.005 kj/kg K and inlet conditions to be at 100 kpa and 27 0 C. Determine the power the output of the turbine and the diameter of the inlet pipe. EME-303/ Mr. Arun Sharma,Mr.Ajay Kr.Verma Date:

5 B.Tech. [SEM III (ME-31, 32, 33,34,35 & 36)] QUIZ TEST-1 Time: 1 Hour THERMODYNAMICS Max. Marks: 30 (EME-303) Note: Attempt All Questions. Q1). Air is trapped in a piston cylinder machine initially p 1 =100kPa, v 1 =2x10 (-3) m 3. The spring exerts no force on the piston in the initial position. The atmospheric pressure is 100 KPa and the area of the piston is 0.018m 2. The air expands slowly till its volume is v 2 =3x10 (-3) m 3 during the process the spring exerts a force on the piston f=-kx where k=16.2x10 3 N/m Neglecting any friction between the piston and cylinder wall. Determine the final pressure of air and work done by the air on the piston (Question-3) [5] Q2) The Temp. t on a thermometric scale is defined in terms of property k by the relation by the relation Where a and b are the const. The value of K are found to be 1.83 and 6.78 at the ice point and the steam point the temperature of which are assigned the numbers 0 and 100 respectively. Determine the temperature corresponding to of reading of K equal to 2.42 on thermometer. (Question-8) [5] Q1) The heat at constant pressure of a certain system is a function of temperature only and may be expressed as C p = / (t+100) J/ 0 C Where t is the temperature of the system in 0 C.The system is heated while it is maintained at pressure of 1 atmosphere until its volume increases from 2000 cm 3 to 2400 cm 3 and its temperature increases from 0 0 C to C. (a) Find the magnitude of the heat interaction. (b) How much does the internal energy of the system. Q.2) A blower handles 1 kg of air at 20 0 C and consume a power of 15kW. The inlet and outlet velocities of air are 100 m/s and 150 m/s respectively. Find the exit air temperature, assuming adiabatic condition. Take C p =1.005 kj/kg-k. Q.3) In a gas turbine the gas enter at the rate of 5 kg/s with the velocities of 50 m/s and enthalpy of 900 kj/kg and leaves the turbine with a velocities of 150 m/s and enthalpy of 400 kj/kg. The loss of heat from the gases to the surrounding is 25 kj/kg. Assuming for gas R=0.287 kj/kg K and C p =1.005 kj/kg K and inlet conditions to be at 100 kpa and 27 0 C. Determine the power the output of the turbine and the diameter of the inlet pipe. X EME-303/ Mr. Arun Sharma,Mr.Ajay Kr.Verma Date:

6 B.Tech. [SEM III (ME)] QUIZ TEST-2 THERMODYNAMICS Time: 1 hour (EME-303) Max. Marks: 30 Note: All questions are compulsory. Q1. Two kg of water at 80 0 C are mixed adiabatically with 3kg of water at 30 0 C in a constant pressure process of 1 atm. Find the increase in entropy of the total mass of water due to mixing process( C p of water =4.187kJ/kg K) (Q.No.2) [5] Q2. Two kg of air at 500kPa, 80 0 C expands adiabatically in a close system until its volume is doubled and its temp become equal to that of surrounding which is at 100kPa, 5 0 C for this process determine (a) the maximum work (b) the change in availability (c) the irreversibility for air take C v =0.718kJ/kg K, u=c v T where C v is constant, and pv=mrt where p is pressure in kpa and V volume in m 3,m mass in kg and R=0.287kJ/kgK, and T temperature in K. (Q.No.12) [2+2+1] Q.1. Define the term available energy and unavailable energy. M 1 kg of water at T 1 is isobarically and adiabatically mixed with M 2 kg of water at T 2 (T 1 >T 2 ). Show that for equal masses of water, the entropy change of the mixture is given by (ds) universe =2MC p ln[(t 1 +T 2 )/2(T 1 T 2 ) 1/2 and prove that the change is necessarily positive. [3+5] Q2. Find the irreversibility associated with expansion process of air through a very small opening in pipe from pressure and temp of 8 bar and 600K to a pressure of 1.2 bar. Assume air to be an ideal gas and temperature of surroundings to be 298 K. Q.3.A lump of steel of mass 8 Kg at 100 K is dropped in 80 Kg of oil at 300K. Make calculations for the entropy change of steel, the oil and the universe. Take specific heats of steel and oil as 0.5kJ/kgK and 3.5kJ/kgK, respectively. [2+2+2] EME-303/ Mr. Ajay Kr. Verma, Mr. Arun Sharma Date: 18 / 11/ 2013

7 B.Tech. [SEM III (ME)] QUIZ TEST-2 THERMODYNAMICS Time: 1 hour (EME-303) Max. Marks: 30 Note: All questions are compulsory. Q1. A reversible heat engine has heat interaction from three reservoir at 600 K, 700 K and 800 K. the engine rejects 10kJ/s to the sink at 320 K after doing 20 kw of work.the heat supplied by reservoir at 800 K is 70%of the heat supplied by reservoir at 700 K then determine the exact amount of heat interaction with each high temperature reservoir. (Q.No.3) [5] Q2. Find the change in entropy of steam generated at C from 5 kg of water at 27 0 C and atmospheric pressure.take specific heat of water to be 4.2 kj/kg K,Heat of vaporization at c as 2260 kj/kg and specific heat for steam given by: C P =R ( T+0.14T 2 ) (Q.No.1) [5] Q.1. Define the term available energy and unavailable energy. M 1 kg of water at T 1 is isobarically and adiabatically mixed with M 2 kg of water at T 2 (T 1 >T 2 ). Show that for equal masses of water, the entropy change of the mixture is given by (ds) universe=2mc p ln[(t 1 +T 2 )/2(T 1 T 2 ) 1/2 and prove that the change is necessarily positive. [3+5] Q2. Find the irreversibility associated with expansion process of air through a very small opening in pipe from pressure and temp of 8 bar and 600K to a pressure of 1.2 bar. Assume air to be an ideal gas and temperature of surroundings to be 298 K. Q.3.A lump of steel of mass 8 Kg at 100 K is dropped in 80 Kg of oil at 300K. Make calculations for the entropy change of steel, the oil and the universe. Take specific heats of steel and oil as 0.5kJ/kgK and 3.5kJ/kgK, respectively. [2+2+2] EME-303/ Mr. Ajay Kr. Verma, Mr. Arun Sharma Date: 18 / 11/ 2013

8 B.Tech. [SEM III (ME)] QUIZ TEST-2 THERMODYNAMICS Time: 1 hour (EME-303) Max. Marks: 30 Note: All questions are compulsory. Q1. A heat engine receive reversibly 420 kj/ cycle of heat from a source at C and rejects heat reversibly to sink at 27 0 C. There are no other heat transfers. For each of the three hypothetical amount of heat rejected in (a),(b)&(c) below, compute the cyclic integral of dq/t from these results show which case is irreversible, which reversible, and which is impossible: (a) 210 kj/cycle rejected (b) 105kJ/ cycle rejected (c) 315 kj/ cycle rejected. (Q.No.5) [2+2+1=5] Q2. In a certain process, a vapor, while condensing at C, transfer heat to water evaporating at C. The resulting steam is used in power cycle which rejects heat at 35 0 C.What is the fraction of available energy in the heat transferred from the process vapour at C that is lost due to the irreversible heat transfer at C. (Q.No.9) [5] Q.1. Define the term available energy and unavailable energy. M 1 kg of water at T 1 is isobarically and adiabatically mixed with M 2 kg of water at T 2 (T 1 >T 2 ). Show that for equal masses of water, the entropy change of the mixture is given by (ds) universe =2MC p ln[(t 1 +T 2 )/2(T 1 T 2 ) 1/2 and prove that the change is necessarily positive. [3+5] Q2. Find the irreversibility associated with expansion process of air through a very small opening in pipe from pressure and temp of 8 bar and 600K to a pressure of 1.2 bar. Assume air to be an ideal gas and temperature of surroundings to be 298 K. Q.3.A lump of steel of mass 8 Kg at 100 K is dropped in 80 Kg of oil at 300K. Make calculations for the entropy change of steel, the oil and the universe. Take specific heats of steel and oil as 0.5kJ/kgK and 3.5kJ/kgK, respectively. [2+2+2] EME-303/ Mr. Ajay Kr. Verma, Mr. Arun Sharma Date: 18 / 11/ 2013

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10 B.Tech. [SEM III (ME)] QUIZ TEST-2 THERMODYNAMICS Time: 1 hour (EME-303) Max. Marks: 30 Note: All questions are compulsory. Q1. A system has a heat capacity at const. volume C v =AT 2 where A = J/K 3 The system is originally at 200 K, and a thermal reservoir at 100 K is available.what is the maximum amount of work that can be recovered as a system is cooled down to the temperature of the reservoir. (Q.No.7) [5] Q2. A quantity of air initially at 1bar 300K undergoes two types of interactions : (a) it is brought to a final temperature of 500 K adiabatically by paddle wheel work transfer,(b) the same temperature rise is brought about by heat transfer from a thermal reservoir at 600 K. Take T 0 =300K, p 0 =1 atm. Determine the irreversibility (in kj/kg) in each case and comment on the results. (Q.No.13) [ =5] Q.1. Define the term available energy and unavailable energy. M 1 kg of water at T 1 is isobarically and adiabatically mixed with M 2 kg of water at T 2 (T 1 >T 2 ). Show that for equal masses of water, the entropy change of the mixture is given by (ds) universe =2MC p ln[(t 1 +T 2 )/2(T 1 T 2 ) 1/2 and prove that the change is necessarily positive. [3+5] Q2. Find the irreversibility associated with expansion process of air through a very small opening in pipe from pressure and temp of 8 bar and 600K to a pressure of 1.2 bar. Assume air to be an ideal gas and temperature of surroundings to be 298 K. Q.3.A lump of steel of mass 8 Kg at 100 K is dropped in 80 Kg of oil at 300K. Make calculations for the entropy change of steel, the oil and the universe. Take specific heats of steel and oil as 0.5kJ/kgK and 3.5kJ/kgK, respectively. [2+2+2] EME-303/ Mr. Ajay Kr. Verma, Mr. Arun Sharma Date: 18 / 11/ 2013

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12 B.Tech. [SEM III (ME)] QUIZ TEST-2 THERMODYNAMICS Time: 1 hour (EME-303) Max. Marks: 30 Note: All questions are compulsory. Q1. Water is heated at constant pressure of 0.7 MPa. The boiling point is C. The initial temperature of water is 0 0 C. The latent heat of evaporation is kJ/kg. Find the increase of entropy of water, if the final state is steam. (Q.No.11) [5] Q2. A heat engine is working between starting temperature limit of T 1 and T 2 of two bodies. Working fluid flows at rate m kg/s and has specific heat at constant pressure as C P.determine the maximum obtainable work from engine. (Q.No.4) [5] Q.1. Define the term available energy and unavailable energy. M 1 kg of water at T 1 is isobarically and adiabatically mixed with M 2 kg of water at T 2 (T 1 >T 2 ). Show that for equal masses of water, the entropy change of the mixture is given by (ds) universe =2MC p ln[(t 1 +T 2 )/2(T 1 T 2 ) 1/2 and prove that the change is necessarily positive. [3+5] Q2. Find the irreversibility associated with expansion process of air through a very small opening in pipe from pressure and temp of 8 bar and 600K to a pressure of 1.2 bar. Assume air to be an ideal gas and temperature of surroundings to be 298 K. Q.3.A lump of steel of mass 8 Kg at 100 K is dropped in 80 Kg of oil at 300K. Make calculations for the entropy change of steel, the oil and the universe. Take specific heats of steel and oil as 0.5kJ/kgK and 3.5kJ/kgK, respectively. [2+2+2] EME-303/ Mr. Ajay Kr. Verma, Mr. Arun Sharma Date: 18 / 11/ 2013

13 B.Tech. [SEM III (ME)] SPECIAL QUIZ THERMODYNAMICS Time: 1 hour (EME-303) Max. marks : 30 Note: All questions are compulsory. Q1. A system undergoes a process as : 1-2 isobaric,2-3 polytropic where n=1.4 and 3-1 isothermal where pv=c. Find the v 2 and Net Work.(p 1 =400kPa,p 2 =100kPa,V 1 =0.1m 3 ) (Q.No.5) [2+3] Q2. The properties of certain fluid are related as follows U= t, p.v=0.287(t+273) Where u is the specific internal energy (kj/kg), t is in C, p is pressure (kn/m2) and v is specific volume (m3/kg). For this fluid find C v and C p. (Q.No.1) [2.5=2.5=5] Q.1.. A gas contained in a cylinder is compressed from 1 MPa and 0.05m 3 to 2MPa. Compression is governed by pv 1.4 =constant.internal energy of a gas is given by : U=7.5pV-425 kj Where p is pressure in kpa and V is volume in m 3 Determine the heat, work, and change in internal energy assuming compression process is isentropic. [3+3+2=8] Q2. In isentropic flow through nozzle, air flows at the rate of 600 kg/hr. at inlet to the nozzle, pressure is 2MPa and temperature is C. The exit pressure is 0.5 MPa. Initial air velocity is 300 m/s. determines (i) exit velocity of air (ii) inlet and exit area of nozzle. [3+3=6] Q3.Explain the free expansion process and PMM-I EME-303 / Mr. Ajay Kr. Verma Date:

14 B.Tech. [SEM III (ME)] SPECIAL QUIZ THERMODYNAMICS Time: 1 hour (EME-303) Max. marks : 30 Note: All questions are compulsory. Q1. Air initially at 60kPa pressure, 800K temperature and occupying a volume of 0.1 m 3 is compressed isothermally until the volume is halved and subsequently it goes further compression at constant pressure till the volume is halved again. Sketch the process on p-v plot and make calculations for the total work done and total heat interaction for the two processes. Assume ideal gas behavior for air and take C p = 1.005kJ/kg K. (Q.No.2) [3+2=5] Q2. A thermocouple with test junction at t 0 C on gas thermometer scale and reference junction at ice point gives the e.m.f. as mv The mill voltmeter is calibrated at ice and steam point.what will be the reading of this thermometer when the gas thermometer reads 70 0 C. (Q.No.7) [5] Q.1. A compressor is required to provide air at 0.5 MPa and C for a stationary power plant. The air intake is at 0.1MPa and 20 0 C.The out let velocity is 25 m/s.(a) Find the work per unit mass needed for an adiabatic compressor.(b) if the air flow is 0.62 kg /s find the capacity of the motor connected to compressor assuming compressor mechanical efficiency [4+4=8] Q2. Determine the heat transfer and its direction for a system in which a perfect gas having molecular weight of 16 is compressed from kpa,20 0 C to a pressure of 600 kpa following the law pv 1.3 =constant.take specific heat at constant pressure of gas as 1.7 kj/kg K. [3+3=6] Q3. Explain the macroscopic and microscopic approach and quasi-static process. [2+2+2=6] EME-303 / Mr. Ajay Kr. Verma, Mr. Arun Sharma Date:

QUESTION BANK UNIT-1 INTRODUCTION. 2. State zeroth law of thermodynamics? Write its importance in thermodynamics.

QUESTION BANK UNIT-1 INTRODUCTION 1. What do you mean by thermodynamic equilibrium? How does it differ from thermal equilibrium? [05 Marks, June-2015] 2. State zeroth law of thermodynamics? Write its importance