Elements of Mechanical Engineering - Jun 2013

First Year Engineering (P Cycle) (Semester 1)

TOTAL MARKS: 100
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks.

Choose the correct answer for the following :-

1 (a) (i) Lunar is _____ form of energy
(A) Stored
(B) Transitional
(C) Celestial
(D) Capital(1 marks) 1 (a) (ii) Enthalpy is also called as _____
(A) Sufficient heat
(B) Insufficient heat
(C) Total heat
(D) Incomplete heat (1 marks) 1 (a) (iii) Steam pressure is _____ in water tube boilers
(A) Low
(B) High
(C) Medium
(D) Absolute(1 marks) 1 (a) (iv) Feed check valve is a boiler mounting for _____
(A) Safety
(B) Operation
(C) Testing
(D) Security(1 marks) 1 (b) Compare and constant renewable and non renewable energy sources.(6 marks) 1 (c) Enumerate the advantages and disadvantages of superheated steam.(4 marks) 1 (d) Explain briefly air preheater superheater and Chimney with respect to boiler.(6 marks)

Choose the correct answer for the following :-

2 (a) (i) An example for a reaction turbine is
(A) Laval turbine
(B) Curtis turbine
(C) Zoelly turbine
(D) Parson's turbine(1 marks) 2 (a) (ii) The weight to power ratio of a gas turbine is
(A) High
(B) Less
(C) Moderate
(D) Equal(1 marks) 2 (a) (iii) Draft tube is a _____ steel pipe
(A) Closed
(B) Open
(C) Converging
(D) Diverging (1 marks) 2 (a) (iv) Kaplan turbine is a _____ head turbine
(A) High
(B) Low
(C) Medium
(D)Simple (1 marks) 2 (b) With a neat sketch, explain the working principle of an impulse turbine.(6 marks) 2 (c) List any four differences between closed cycle and open cycle gas turbine.(4 marks) 2 (d) Define redial flow, axial flow and mixed flow with respect to water turbine.(6 marks)

Choose the correct answer for the following :-

3 (a) (i) Flywheel is used as an energy _____
(A) Receiver
(B) Reservoir
(C) Mixer
(D) Multiplier(1 marks) 3 (a) (ii) Mechanical effieciency of a four-stroke engine is
(A) Medium
(B) High
(C) Low
(D) Balanced(1 marks) 3 (a) (iii) The output shaft in IC engines is
(A) Camshaft
(B) Crankshaft
(C) Rotary shaft
(D) Axial shaft(1 marks) 3 (a) (iv) In C.I. engines, charge means
(A) Air and fuel
(B) Only fuel
(C) Air and water
(D) Only air(1 marks) 3 (b) List any four differences between two-stroke and four-stroke engines.(4 marks) 3 (c) A six cylinder 4-stroke I.C. engines develops 50 kW of indicated power at mep of 700 kPa. The bore and stroke length are 70mm and 100mm respectively. If the engine speed is 3700 rpm. Find the average misfires per unit time.(6 marks) 3 (d) Draw a schematic diagram of I.C. engines and name the parts.(6 marks)

Choose the correct answer for the following :-

4 (a) (i) Brine is an example for
(A) Coolant
(B) Effluent
(C) Deodourant
(D) Refrigerant(1 marks) 4 (a) (ii) The value of COP is greater than
(A) Infinity
(B) Ten
(C) Unity
(D) Hundred(1 marks) 4 (a) (iii) A thermostat in A.C. is used to control
(A) Pressure
(B) Temperature
(C) Volume
(D) Efficiency (1 marks) 4 (a) (iv) The viscosity of an ideal refrigerant should be
(A) Low
(B) High
(C) Moderate
(D) Unity(1 marks) 4 (b) Mention the user of any four refrigerants.(4 marks) 4 (c) With a neat sketch, explain the working o a vapour absorption refrigerator.(6 marks) 4 (D) List the differences between vapour compression refrigeration and vapour absorption refrigeration.(6 marks)

Choose the correct answer for the following :-

5 (a) (i) Compound side swiveling method is used to produce
(A) Hole
(B) Threads
(C) Knurl
(D) Taper(1 marks) 5 (a) (ii) Lathe Dog is
(A) A part
(B) A component
(C) An accessory
(D) An assembly(1 marks) 5 (a) (iii) _____ is an operation to produce a conical surface at the end of a predrilled hole
(A) Counter Boring
(B) Counter sinking
(C) Tapping
(D) Reaming (1 marks) 5 (a) (iv) The supporting section (core) of a drill is called
(A) Web
(B) Tang
(C) Land
(D) Margin (1 marks) 5 (b) With a neat sketch, explain the principle and operation to produce a 'taper' on lathe by tail stock set over method.(6 marks) 5 (c) Differentiate between cross slide and compound slide.(4 marks) 5 (d) With a neat sketch, explain the operation of a radial drilling machine.(6 marks)

Choose the correct answer for the following :-

6 (a) (i) Conventional milling is also called
(A) End milling
(B) Climb milling
(C) peripheral milling
(D) Up milling (1 marks) 6 (a) (ii) The milling process used to produce V-blocks is called
(A) Form milling
(B) Slot milling
(C) Angular milling
(D) slab milling (1 marks) 6 (a) (iii) Flint is an example for a _____ abrasive
(A) Artificial
(B) Natural
(C) Strong
(D) Weak(1 marks) 6 (a) (iv) The bond used for manufacturing clastic grinding wheels is called
(A) Shellac
(B) Vitrified
(C) Resinoid
(D) Oxy-chloride(1 marks) 6 (b) Differentiate between up milling and down milling.(6 marks) 6 (c) List any four differences between horizontal milling machine and vertical milling machine.(4 marks) 6 (d) With a neat sketch, explain the principle of centreless cylindrical grinding.(6 marks)

Choose the correct answer for the following :-

7 (a) (i) Spelter is used in
(A) Welding
(B) Brazing
(C) Soldering
(D) Electroplanting (1 marks) 7 (a) (ii) _____ is used as flux in welding
(A) Sodium phosphate
(B) Sodium carbonate
(C) Sodium silicate
(D) Sodium chloride(1 marks) 7 (a) (iii) A good lubricant should be
(A) Highly volatile
(B) Non-volatile
(C) Less volatile
(D) Moderately volatile (1 marks) 7 (a) (iv) Collar bearing is an example for
(A) Radial bearing
(B) Journal bearing
(C) Thrust bearing
(D) Sleeve bearing (1 marks) 7 (b) With a neat sketch explain a foot step bearing.(6 marks) 7 (c) Explain splash lubricantion with a neat sketch.(6 marks) 7 (d) Differentiate between welding and brazing.(4 marks)

Choose the correct answer for the following :-

8 (a) (i) V-belts are,
(A) Repairable
(B) Not repairable
(C) Quickly repairable
(D) Easily reapairable (1 marks) 8 (a) (ii) Belts transmit motion by _____
(A) Friction
(B) Abrasion
(C) Suction
(D) Expulsion (1 marks) 8 (a) (iii) The surface of the tooth below the pitch circle is called _____
(A) Clearance
(B) Flank
(C) Backlash
(D) Face(1 marks) 8 (a) (iv) Module indicates the _____ of the pitch,
(A) Whole
(B) Total
(C) Total
(D) Integration(1 marks) 8 (b) Differentiate between an open belt drive and cross belt drive.(4 marks) 8 (c) Enumerate the advantages and disadvantages of gear drives.(6 marks) 8 (d) A V-belt drive transmits 10 kW power at 240 rmp. The grooved pulley has a mean diameter of 1.2 and groove angle of 45°. Taking ?=0.3 and angle of lap equal to ? radians. Determine the tensions on each side of the belt.(6 marks)