Mahatma Gandhi University (MGU) 2007 B.Tech Electronics and Communications Engineering S1S2 - Question Paper

B.TECH DEGREE exam JULY/AUGUST 2007
First and 2nd Semester
BASIC MECHANICAL ENGINEERING
(Regular/Supplementary)
[Common to all branches]

Time: 3 Hours Maximum: 100 Marks

ans all ques.
Part A

1. describe specific heat. Why gases have 2 specific heats?

2. Derive an expression for the heat transfer in a polytropic process.

3. How IC engines are classified?

4. With a sketch, discuss the vapour compression refrigeration system.

5. find an expression for the length of a cross belt drive.

6. elaborate the advantages and disadvantages of a rope drive?

7. What is meant by ‘Direct energy conversion systems’?

8. Differentiate ranging from an impulse turbine and a reaction turbine.

9. What is the use of a chuck? Mention the various chuck used in a lathe.

10. What is the purpose of using additives in moulding sand?

[10 × four = 40 marks]


Part B

11. (a) Derive an expression for the air standard efficiency of a diesel cycle
Or
(b) two kg of an ideal gas occupies a quantity of 0.3m3 at 10 bar pressure and 500K temperature. When this gas expands polytropically (PV1.2=C).The internal energy reduces by 300KJ.Presuming adiabatic exponent r =1.4, determine.
a) Specific gas constant
b) Final temperature and pressure of the gas.
c) Heat and work inter actions across the system boundary

12. (a) With neat sketch, discuss the various kinds of lubrication systems used in I.C engines.
Or
(b)What is meant by air conditioning? Differentiate ranging from winter air conditioning and summer air conditioning

13(a) Derive an expression for the ratio of tensions for flat belt passing over a pulley.
Or
(b)Derive the formula for the minimum number of teeth in a spur gear.

14(a) Draw a general layout of a Thermal power plant and discuss it.
Or
(b)Why are steam turbine compounded? discuss with sketches the various methods of compounding.

15(a) Briefly explains the working principle in milling with the help of a neat sketch. discuss horizontal milling machine.
Or
(b)What are the reasons for providing trend allowances? discuss the important trend allowances.

[5 × 12 = 60 marks]

Earning:   Approval pending.