Elements of Mechanical Engineeringpatelpath.yolasite.com/resources/EME_Important Questions... ·...

110006

Amrat Patel, Hitesh Solanki, Nainesh Patel, Afzal Bhat, Aparajita SahuAsst. Professors

Elements of Mechanical Engineering

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Smt Shantaben Haribhai Gajera Charitable Trust, SuratLAXMI INSTITUTE OF TECHNOLOGY, SARIGAM

BE – I, Semester – II (Section: A, B & C)Important Questions asked in Universities (GTU, GU & HNGU)

Subject: - Elements of Mechanical Engineering (110006)

INTRODUCTION

1. Define prime movers. Classify the prime movers. (July-00, Nov-01, June-05, Nov-05, GTU June-09, Sept-09, Dec-10R, GTU Jan-11)

2. Explain different sources of energy used by prime movers. (Nov-00, June-08, GTU March-09, GTU Jan-11)3. Define zeroth law of thermodynamics, and First law of thermodynamics. (July-00, Nov-02, June-06, GTU June-

09, Sept-06, GTU Dec-10R)4. What is pressure? How it is measured? What is standard atmospheric pressure? What is vacuum? What is its unit?

(July-00, Nov-02)5. What is heat? What is positive and negative heat? What are the factors on which the heat flow depends? ( July-00,

June-06)6. What is work? Mention similarities between heat and work. (Nov-00, Aug-01, June-05)7. What is energy and energy conservation? What are the various types of energy? (July-00, Nov-00, July-04)8. Explain the terms : melting point, boiling point and critical point.(Nov-00, June-05, Nov-05)9. What is internal energy of a closed system? Derive its expression, (Aug-01)10. Explain different types of systems with a neat sketch. (Aug-01, July-02, Nov-02, July-03, 04, June-05, July-07)11. Explain process, path and state.(Aug-01, June-06)12. Define the terms (i) specific heat of a substance (ii) brake thermal efficiency (GTU Jan-11)13. What is path function and point function? (Nov-01, 02)14. What is flow work? Explain. (Nov-01)15. Define thermodynamic work? How work done is designated? Why? Which sign convention is used for work?

(July-02) 16. Define: system, surroundings and boundary. Also explain fixed and movable boundary (July-03, June-06)17. Differentiate between

a) System and surrounding. (July-04)b) Intensive and Extensive properties (June-07)c) Heat and Work (June-08)d) Higher C.V and lower C.V of fuel (GTU Dec-10R)e) Lignite and bituminous coal (GTU Dec-10R)

18. Define power, temperature (GTU Dec-10R), enthalpy, latent heat (GTU Dec-10R), Boundary (GTU Dec-10R), Specific volume of steam, Dryness fraction of steam & internal energy.

19. Which common solid fuels? Write in brief about each of them Define calorific value of fuel (GTU Jan-11)

PROPERTIES OF STEAM

1. With neat sketch explain construction and working of throttling calorimeter. (July-04, June-05, 08, GTU Dec-10R)

2. Explain what is internal heat of evaporation (July-02, Nov-02, June-08)3. What is dryness fraction and wetness fraction of a steam? (Nov-00, 05, July-04, June-05, 06, 08, GTU March-

09R)4. With a neat sketch describe the working of combined separating and throttling calorimeter. (Aug-01, June-06,

GTU March-09R)5. With a neat sketch describe the construction and working of Barrel calorimeter. Also explain how dryness fraction

of steam can be determined by it. (July-03)

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6. Define the following terms: (Nov-05, June-06, 08)(i) Enthalpy of dry and saturated steam (GTU Jan-11)(ii) Dry saturated steam (GTU Jan-11)(iii) Degree of superheat (iv) Enthalpy of evaporation(v) Priming(vi) Superheated steam

7. State the difference between:Superheated steam and wet steam (June-05)

8. Prove that dryness fraction + wetness fraction = 19. Define Degree of superheat & Dryness fraction of steam.10. Determine dryness fraction of steam supplied to a separating and throttling calorimeter.

Water separated in separating calorimeter = 0.45 kgSteam discharge from throttling calorimeter = 7 kgSteam pressure in main pipe = 1.2 MPaBarometer reading = 760 mm of HgManometer reading = 180 mm of HgTemperature of steam after throttling = 140 oCTake Cps = 2.1 kJ/kg K.

11. A Steam Generator evaporates 18000 Kg/Hr of steam at 12 bar Pressure and steam is 97% dry. Feed water temperature = 105 °C. Coal is fired at the rate of 2050 Kg/Hr. C.V. of Coal is 27400 KJ/Kg. Calculate.(i) Heat Supplied per Hour.(ii) Thermal Efficiency.(iii) Actual Evaporation (GTU June-09)

12. The following information is available from test of a combined separating and throttling calorimeter. Pressure of steam in a steam main = 9.0 barPressure after throttling = 1.0 barTemperature after throttling =115 degree centigradeMass of steam condensed after throttling = 1.8 KgMass of water collected in the separator = 0.2 Kg.Calculate the dryness fraction of the steam in the main. (GTU Sept-09)

13. A sample of wet steam at a pressure of 25 bar absolute has dryness fraction 0.80. Determine its enthalpy and internal energy. (GTU Dec-08)

14. Combined separating and throttling calorimeter is used to find out dryness fraction of steam. Following readings were taken:Main pressure = 12 bar ab.Mass of water collected in separating calorimeter = 2 kgMass of steam condensed in throttling calorimeter = 20 kgTemperature of steam after throttling = 110 0CPressure of steam after throttling = 1 bar ab.Assume Cp of steam = 2.1 kJ/kg KCalculate dryness fraction of steam. (GTU Dec-08)

15. Determine the enthalpy and internal energy of 1 Kg of steam at a pressure 10 bar(abs.), (i)when the dryness fraction of the steam is 0.85 (ii) when the steam is dry and saturated (iii) when the steam is superheated to300ºC. Neglect the volume of water and take the specific heat of superheated steam as 2.1 KJ/KgK.

16. What is a superheated steam? How much heat is added to convert 3 kg of water at 300C into steam at 8 bar and 2100C? Take specific heat of superheated steam as 2.1 KJ/Kg-K and that of water as 4.186 KJ/Kg-K (GTU Jan-11)

PROPERTIES OF GAS


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1. State the following Charles Law, Boyles Law, Characteristic gas equation.2. Derive characteristics equation of a perfect gas.3. Prove the following relations when a gas is compressed according to the law PV=C (July-00, July-03, GTU

Dec-10R)

=

=

Hence or otherwise prove that

= γ

4. For polytropic, with usual notations, prove the following : (Aug-01, July-03)

(i) (July-04)

(ii) Work done = , where r =

5. By using Joule’s law and first law, derive the relation for 1 and 1 1 for polytropic process (July-02,

03)6. Define adiabatic process. Derive the relation between P, V and T for this process. Also derive the expression for

workdone and change in internal energy for this process. (GTU Jan-11, Nov-02)7. For adiabatic process prove that PV=C (Nov-00, 05 July-04, May-05, June-06, 08)8. With usual notations prove that Cp – Cv = R. (Nov-02, June-07, GTU June-09, March-09R)9. What is N.T.P and S.T.P? (Nov-02)10. Why gases have two specific heats? (Nov-01, June-06)11. Derive an expression of work done when a gas is expanded as per law PV=C with usual notations. (Nov-01,

July-02, June-08)12. Write about combined gas law, gas constant and non flow process.13. What is isothermal process? Derive an expression for the work done during the isothermal process.14. 0.15 m3 of air at pressure of 900 Kpa and 300 °C is expanded at constant pressure to 3 times its initial volume. It is

expanded polytropically following the law PV1.5 =C and finally compressed back to initial state isothermally. Calculate heat received, heat rejected, efficiency of cycle.

15. An ideal gas is heated from 25oC to145oC. The mass of gas is 2 kg. Determine (i) Specific heats (ii) change in internal energy, (iii) change in enthalpy. Assume R = 267 J/Kg K and γ =1.4 for the gas.

16. A gas whose pressure, volume, and temperatures are 2.75 bar, 0.09m3 and 185°C respectively has the state changed at constant pressure until its temperature becomes 15°C. Calculate Heat Transferred & Work Done during the process. Take R= 0.29 KJ/Kg K, and Cp = 1.005 KJ/Kg K. (Nov-00, GTU June-09)

17. A cylinder contains 0.6 m3 of gas at a pressure of 1.0 bar and 900 0C. The gas is compressed to a volume of 0.18 m3 according to law pvn = C. The final pressure is 5.0 bar. Assuming R=0.287 kJ/kg K and γ = 1.4Calculate:

(i) The mass of gas(ii) The value of index ‘n’ for compression(iii) The change of internal energy of gas (GTU Dec-08)


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HEAT ENGINES

1. Prove that the efficiency of the Carnot engine working between the temperature units T1 and T2 is equal to .

(Nov-00, July-04, Nov-05, June-07, GTU Dec-08)2. Explain working of Rankine cycle with P-V diagram. Derive the formula for efficiency of Rankine cycle. (Nov-

00, GTU Jan-11)3. Derive the equation of efficiency for Diesel Cycle with usual notations. (Aug-01, July-02, GTU March-09R)4. List various source of energy (June-08)5. Prove with usual notations the expression for the efficiency of an air standard Otto cycle.

The engine is working on ideal Otto cycle. Calculate the air standard efficiency. (Nov-00, 01, June-05, 06, GTU June 09, 09R)

6. State the assumptions & limitations of Carnot Cycle and derive the equation of efficiency for Carnot Cycle.7. State the assumptions & limitations of Carnot Vapour Cycle and derive the equation of efficiency for Carnot

Cycle.8. In air standard Otto Cycle the Maximum and Minimum temperatures are 1673 K and 288 K. The heat supplied per

Kg of air is 800 KJ. Calculate.(i) The Compression Ratio.(ii) Efficiency.(iii) Max & Min Pressures.Take Cv = 0.718 KJ/Kg K & γ = 1.4 for air. (GTU June-09)

9. In an Otto cycle the compression ratio is 8.The temperatures at the beginning of compression and at the end of heat supply are 310 K and 1600 K respectively. Assume γ = 1.4 and Cv = 0.717 kJ/kg K.Find:(i) Heat Supplied(ii) Efficiency of the cycle. (GTU Dec-08)

10. The compression ratio of an oil engine working on Diesel Cycle is 15. Cut off takes place at 12 % of the working stroke. The air is drawn in to cylinder at 100 kPa and 270C. Assume Cp=1.006 kJ/kg K and Cv =0.717 kJ/kg K. Calculate:(i) Temperature at the end of compression(ii) Pressure at the end of compression(iii) Air std. efficiency of the cycle. (GTU Dec-08)

11. In an ideal diesel cycle the temperature at beginning and at the end of Compression are 57.0 degree centigrade and 603 degree centigrade respectively. The temperatures at beginning and end of expansion are 1950 degree centigrade and 870 degree centigrade respectively. Determine the ideal efficiency of the cycle if pressure at beginning is 1.0 bar. Calculate: maximum pressure in the cycle. (GTU Sept-09)

STEAM BOILERS

1. Describe with neat sketch: (i) Water level indicator (July-00, Nov-01, July-02, July-03, June-08) (ii) Pressure gauge (July-03, Aug-01, June-05) (iii) Blow of Cock (July-00, Nov-02, July-04)

2. Describe the working of a Lancashire boiler with neat sketch. (July 2000)3. Discuss construction and working of cochran boiler with sketch. (Nov-01, July-03, July-04, Nov-05, June-06,

June-08, GTU Sept-09R, March-10R, GTU Jan-11)


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4. Explain with neat sketch the construction and working of babcock and wilcox boiler, advantages, disadvantages and application. (Nov-00, June-07, GTU March-09R, Dec-10R)

5. Enlist factors affecting the boiler efficiency.(July-00)6. What is economiser? Why it is used in a boiler plants? What are the advantages and disadvantages of economiser?

(Nov-01)7. Explain equivalent evaporation (Nov-02, GTU June-09)8. Short note on Spring Loaded Safety Valve (July 2007, GTU 2009)9. Feed Water Heater or Green’s Economiser (June-07, GTU Sept-09R)10. List various Mounting and accessories (GTU Dec-08, Sept-09R)11. What is the difference between mountings and accessories of a boiler? (GTU Jan-11)12. Comparison between

(i) Natural circulation and Forced circulation in boiler.(ii)Fire Tube and Water Tube Boiler (June-07, June-08, GTU Dec-08, Sept-09R)

13. Write a short note on: (Nov-00, July-02, June-05, June-08)(i) Fusible plug (GTU March-10) (ii) Lever loaded safety valve14. Explain the function of following mountings and accessories with neat sketch :

(i) Air preheater. (ii) safety valve (iii) Superheater (iv) Economiser (GTU Dec-10R)15. Explain with neat sketch the constructional details and working of the pressure gauge (GTU March-10R)16. Explain with neat sketch the constructional details and working of the Ramsbottom type spring loaded Safety

Valve. (GTU June-09)17. What are high pressure boilers? State their advantages and disadvantages of high pressure boilers( GTU Dec-10R)18. What are high pressure boilers? State their advantages. (GTU Dec-10R)19. Short note on Lamount boiler.20. A steam generator evaporates 18000 kg of water per hour at 10 bar ab. pressure. The steam is 97 % dry. Feed

water temperature is 400 0C. Coal is fired at a rate of 2050 kg per hour, having calorific value 28000 kJ/kg. (GTU Dec-08)Calculate:(i) Thermal efficiency(ii) Equivalent evaporation per kg of coal.

21. A boiler generates 7.5 kg of steam/kg of coal burnt at a pressure of 11 bar. The feed water temperature = 70 0C.

= 75%, Factor of evaporation = 1.15. Take Cps = 2.1 KJ/Kg K. Calculate: (1) Degree of superheat and

temperature of steam generated (2) Calorific value of coal KJ/Kg (3) Equivalent evaporation in Kg of steam/kg of coal. (GTU Sept-09R)

22. What is equivalent evaporation from and at 100 0C? ExplainIn a boiler test 1200 kg of coal are consumed in 24 hrs. The mass of water evaporated is 1200 kg. Steam pressure is 7 bar. The feed water temperature is 40 0C, Calorific value of the coal = 30000 KJ/Kg. The steam is dry and saturated. Calculate: (1) Equivalent evaporation (from and at) 100 0C. (2) Boiler efficiency. Abstract from steam tablesPressurebar

Temp0C

Specific Enthalpy, KJ/Kg

hf hg

70.07335

164.9640

679.06167.45

2762.02574.4

Equivalent evaporation from and at 100 0C. (Nov-00, June-05)

INTERNAL COMBUSTION ENGINE

1. State the advantages of I.C engines and external combustion engines. (Nov-02)2. Comparison between Petrol and Diesel Engine. (Nov-02, June-07, GTU Sept-09R)Free study materials for subjects Elements of Mechanical Engineering, Engineering Graphics

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3. How do you classify I.C engines? Explain. (July-02, June-05, Nov-05, June-08, GTU Dec-10R)4. With neat sketch explain working of two stroke petrol engine. (Nov-01, June-07, June-08)5. What are the functions of (i) injector in diesel engine and (ii) carburettor in petrol engine? (GTU Jan-11)6. Make comparison between 2–stroke and 4–stroke cycle I. C. Engines. (July-00, 02, June-05, 06, 08, GTU Dec-

09, March-09R)7. Describe the construction and working of a Spark plug. Where it is used? Why? (Aug-01)8. Explain following terms related to I. C. Engines, (June-08) (i) Indicated power (ii) Indicated thermal efficiency (iii) Brake power (iv) Friction power (v) Mechanical efficiency (vi) Brake specific fuel consumption9. With a neat sketch explain four stroke cycle I.C engines.(Nov-00, July-03, July-04, Nov-05)10. Give function of following components used in I. C. engines, (i) Cylinder (ii) Piston (iii) Connecting Rod (iv) Crank (v) Fly Wheel (vi) Crank Shaft.11. State the function of I. C. Engines and classify the I. C. Engines in detail.12. Explain with neat sketch working of 4-Stroke diesel engine. (GTU Jan-11)13. Why petrol engines are called as S. I. Engines? And why Diesel engines are called as C. I. Engines?14. Define compression ratio. State the probable value of compression ratio used for petrol as well as Diesel engines.15. A six cylinder 4 Stroke IC Engine is to develop 89.5 KW indicated power at 800 rpm. The stroke to bore ratio is

1.25:1. Assuming mechanical efficiency of 80% and brake mean effective pressure of 5 bar. Determine the diameter and stroke of the Engine.(GTU June-09)

16. A four cylinder of 4-Stroke petrol engine develops 200 KW brake power at 25000 rpm. Stroke to bore ratio is 1.2. If mean effective pressure is 10 bar and mechanical efficiency is 81%, Calculate bore and stroke of the engine. Also calculate indicated thermal efficiency and brake thermal efficiency if 65 kg/hr of petrol is consumed having calorific value of 42000 kJ/Kg. (GTU Jan-11)

17. Following readings were taken during test of single cylinder four stoke oil engine.(i) Cylinder diameter = 250 mm(ii) Stroke length = 400 mm(iii) Main effective pressure = 6.5 bar(iv) Engine speed = 250 r. p .m.(v) Net load on brake = 1080 Newton(vi) Effective diameter of brake = 1.5 meter(vii) Fuel used per hour = 10 Kg(viii) Calorific value of fuel = 44300 KJ/KgCalculate (1) Indicated power, (2) Brake power, (3) Mechanical efficiency and (4) Indicated thermal efficiency. (GTU Sept-09)

18. The following readings were taken during the test on a single cylinder four stroke, Oil engine :Cylinder diameter = 270 mmStroke Length = 380 mmMean effective pressure = 6 barEngine Speed = 250 rpmNet load on brake = 1000 NEffective mean Diameter of brake = 1.5 mFuel used = 10 Kg/HrC.V. of Fuel = 44400 KJ/KgCalculate: -

(i) Brake Power.(ii) Indicated Power.(iii) Mechanical Efficiency.(iv) Indicated Thermal Efficiency. (GTU June-09)

19. The following results refer to a test on i.c. engine.


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Indicated Power = 42 kWFrictional power = 7 kWEngine speed = 1800 r.p.m.Specific fuel consumption per b.p. = 0.30 kg/kWhCalorific Value of fuel used = 43000 kJ/kgCalculate:(i) Mechanical Efficiency(ii) Brake thermal efficiency(iii) Indicated thermal efficiency (GTU Dec-08)

SPEED CONTROL

1. What is the purpose of governor? Classify the governing methods used in I.C engines and describe quantity method & Quality method of governing. (July-02, June-06, GTU June-09)

2. Explain working of watt governor with neat sketch.(July-03, July-04, GTU Dec-08)3. With neat sketch describe the working of Hartnell governor(June-05, GTU March-09R, Sept-09R )4. Explain: Flywheel using sketch. (June-08, GTU March-10R)5. Explain the function of flywheel with turning moment diagram.(GTU Dec-08)6. What is flywheel? How governor differs from flywheel.(Nov05, GTU Jan-11)7. Differentiate: Governor and flywheel.(GTU Dec-10R)8. State different methods of governing I.C engines and explain anyone.(GTU March-10R, Dec-10R)

PUMPS

1. With a simple sketch explain working of centrifugal pump. (Nov-00, 05, GTU sept-09)2. Explain with neat sketch the working of single acting piston pump (Nov-00, July-04, GTU Dec-08)3. What is priming? Explain with a neat sketch vane pump. (July-02, June-06, 08)4. What is priming? Why is it required for a centrifugal pump? (GTU Jan-11)5. Working of double acting reciprocation pump (July-03, June-07)6. What is pump? Classify pump. (July-03, June-07)7. What is function of a pump? (June-07) Explain with neat sketch, working of centrifugal pump (GTU Jan-11)8. Explain : Whirlpool chamber type centrifugal pump with neat sketch (June-08)9. Explain gear pump (June-08)10. Classify centrifugal pump and explain volute type, vortex or diffuser type centrifugal pump. (GTU June-09)11. Explain following terms associated with pumps (GTU Dec-10R)

i) Priming in Pumps ii) Head iii) Air chamber

AIR COMPRESSORS

1. Mention at least four industrial and commercial use of compressed air (July-00, June-05, 08, GTU March-09R)

2. With a simple sketch explain the working of Vane type compressor. (July-00)3. For a single stage compressor, with clearance volume, with usual notations prove that work required to compress

the air/cycle is given by work done/cycle= P1 (V1-V4) (July-00, 02, 03, June-05)

4. With a simple line sketch explain the working of single stage reciprocating compressor. (Nov-00)5. Derive an expression for work done/cycle for air compressor with usual notation neglecting clearance volume,

(Nov-01, 05, GTU June-09, Sept-09R)6. How compressors are classified? (Nov-02)7. What are the uses of compressed air? (GTU Jan-11)


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8. Define volumetric efficiency with P-V diagram with usual notations, prove that volumetric efficiency of

reciprocating compressor is : (July-04, June-07, GTU Dec-08)9. Differentiate between reciprocating and rotary air compressor. (July-04)10. What is clearance volume? Why is it required in a compressor? ( Nov-00, June-06, June-07)11. In air compressor air enters at 1.013 bar and 27 degree centigrade having volume 5.0 m3/kg and it is compressed

to 12 bar isothermally. Determine(i) Work done(ii) Heat transfer and(iii) Change in internal energy (GTU Sept-09R)

12. Air is to be compressed in a single stage reciprocating compressor from 1.013 bar and 15°C to 7 bar. Calculate the indicated power required for a free air delivery of 0.3 m3 / min when the compression process is. (GTU June-09)(i) Isentropic (ii) Reversible Isothermal(iii) Polytropic with n= 1.25. What will be the delivery temperature in each case? Neglect clearance.

13. A single stage, single cylinder reciprocating air compressor with negligible clearance takes 1 m3 of air per minute at 1.013 bar and 15 0C. The delivery pressure is 7 bar. Assuming law of compression pv1.35 = C, R=0.287 kJ/kg K. Calculate:(i) Mass of air delivered per minute(ii) Delivery temperature(iii) Indicated Power(iv) Isothermal efficiency (GTU Dec-08)

14. A single stage reciprocating air compressor is required to compress 1Kg of air from 1 bar to 5 bar. Initial temperature of air is 27 °C. Calculate work required for isothermal, and poly tropic compression with n=1.25 (GTU Dec-10R)

15. What is compressor? Air is compressed through a pressure ratio of 10 from a pressure of 1 bar in a single stage air compressor. Free air delivery is 3 m3/min. Swept volume= 14 litres. Index of compression is 1.3. Neglect clearance volume. Calculate (1) power required in KW (2) Rotational speed of the compressor.

REFRIGERATION & AIR CONDITIONING

1. What do you understand by 1 Ton of refrigeration? OR What is refrigeration? (July-00, Nov-01, July-02, GTU Dec-08)

2. What is refrigerating effect? (Nov-01, July-02, GTU Dec-08)3. What is Co-efficient of Performance (C.O.P) as applied to refrigeration cycle? (July-00, GTU Jan-11)4. What is refrigerant? (GTU Dec-08) State their desirable characteristics of refrigerants. (July-00, July-02, July-

04, Nov-05, June-06, June-07, GTU March-09R)5. What is refrigerating effect? What is one ton refrigeration?6. With neat sketch describe the working of vapour compression refrigeration cycle. What is refrigerant and why it is

used in this cycle? (Nov-00, Aug-01, July-02, Nov-02, 05, July-03, 04, June-05,07, March-09R, GTU Jan-11) (Draw p-h and T-S chart) (GTU June-09).

7. Make comparison between vapour compressions and vapour absorption system(GTU Sept-09R)8. Explain window air conditioner with neat sketch along with its advantages (GTU Sept-09R, Dec-10R)9. What is split air conditioner? State its advantages over window air conditioner.(GTU Dec-08)10. Why air conditioning is required in aircraft? (July-00, Nov-00, 01, June-08, GTU June-09)11. Explain with flow diagram the working of a vapour absorption refrigerator.


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12. Define air conditioning and classify the air conditioning systems. State the basic components of air conditioning system.

COUPLINGS, CLUTCHES & BRAKES

1. How couplings are classified? (July-00, 02, 05, GTU June-09)2. What is clutch? Mention broad classification of clutches. (July-00)3. Give the difference between coupling and clutch. (Nov-00, GTU Dec-08)4. Explain with neat sketch the working of a band brake. (Nov-00, Aug-01)5. With a simple sketch explain the working of disc clutch (Nov-01, July-03, GTU Dec-08)6. With neat sketch describe split-muff coupling. (July-02, June-05)7. Short note on Internal Expanding shoe brake(July-03, July-04, Nov-05)8. Explain oldham coupling. (GTU June-06)9. Explain (i) muff coupling (ii) single plate clutch (iii) band brake (GTU Jan-11)10. Evaluate the statement “clutch is a coupling with on – off switch for transmission of power.”11. Draw neat sketch of following and give only application of each. (i) Flexible coupling (ii) Disc clutch (iii) Band block brake.12. Differentiate between Brake and Clutch. (GTU Dec-10R)13. Write conditions in which universal coupling and centrifugal clutch are used.14. How does the working of a clamp coupling differ from that of a muff coupling?15. Why double block brake is preferred to single block brake?

TRANSMISSION OF MOTION AND POWER

1. Compare individual drive and group drive (GTU Sept-09R)2. Compare belt drive, chain drive and gear drive. (GTU Dec-08, March- 10R)3. List advantages and disadvantages of gear drive (GTU Dec-10R)4. Derive an equation for open belt drive and cross belt drive?5. Derive an equation for ratio of tensions in a belt.6. Short note on: Types of belt drive. (Nov-01, Nov-02, July-04, June-07, GTU March-10R)7. What is a rider pulley? How it works?8. Explain what is a plain bearing? (July-02)9. Explain with neat sketch the working of fast and loose pulley. (Aug-01, June-05, June-06)10. What are bearings? How are they classified? Explain thrust bearing (July-00, July-04, June-08, GTU June-09)11. What is chain drive? How the power is transmitted with a chain drive (July-00)12. What are the elements of power transmission? Mention them (Nov-05, June-08)13. Angular contact and Taper Roller Bearing (July-03)14. Write a short note on: Types of Belts. (Nov-00, July-02)

What are the materials used for belt belts? (GTU Sept-09R)Compare flat and V-belt drive.

15. Write short note on (i) Helical gear. (GTU June-09)(ii) Bevel gear. (iii) Epicyclic gear train.(iv) Worm gear (GTU Jan-11)(v) Rack and pinion (GTU Jan-11)(vi) Cross belt drive (GTU Jan-11)


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16. What do you understand by gear train? Discuss various types of gear train.(GTU Dec-10R)17. Write in detail about transmission of motion and power. (GTU March-09R)

Examples 1:Two pulleys, one 450mm dia. and the other 200 mm dia., on parallel shaft 1.95 m apart are connected by a crossed belt. Find the length of the belt required, between the belt and each pulley. If the drive is open, what length of the belt is needed?Examples 2:A leather belt with cross sectional area of 2250 mm2 is used to drive a cast iron pulley 900 mm in diameter at 336 rpm. If the angle of lap is 120° and the stress in the tight side is 2 MPa, find

a) Effective tension on the tight side of beltb) Centrifugal force acting on the beltc) Effective tension on the slack side of the beltd) Power capacity of the belt

The density of the leather is 980 kg/m3, and the coefficient of friction is 0.35Examples 3:Following are the details of a crossed belt driveDiameter of the driver : 200 mmDiameter of the follower : 400 mmCenter distance of the drive : 2mSpeed of the drive : 400 rpmAngle of contact : 197.3 Determine the length of the belt required. For the drive if tension on tight side is 1.3 kN, and the coefficient of friction between the belt and pulley is 0.25, find the power capacity of the drive.

IMPORTANT ENGINEERING MATERIALS

1. Enlist properties of engineering materials2. Define

a) Ductility (GTU Dec-08, Sept-09Rb) Elasticity (GTU Dec-08)c) Plasticity (GTU Dec-08, Sept-09R)d) Weldability (GTU Dec-08)

3. Explain Physical Properties (GTU June-09) a) Electrical properties b) Thermal propertiesc) Magnetic properties

4. Write about engineering materials. (GTU March-09R)5. Explain in brief the properties (i) elasticity and (ii) hardness of the material.(GTU Jan-11)6. Explain Composite Materials. (GTU June-09)7. State three Engineering application of following materials (GTU Dec-10R)

a) Diamondb) Composite materials.

8. What do you understand by non-metallic materials? Name any six and state their practical importance.9. Describe in brief the various non-ferrous metals along with their applications.10. Short note on

(i) Mild steel (GTU Jan-11) (ii) Plywood (GTU Jan-11) (iii) Fireclay (GTU Jan-11) (iv) Ferrous materials11. Enlist properties of copper? State their applications.


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