JNTU, B.Tech,I-Semester,MECHANICAL AND ELECTRICAL SCIENCE, November ,2008
MECHANICAL AND ELECTRICAL SCIENCE, November 2008
1. (a) Define:
iii. Displacement of an I.C. Engine and mention their units.
(b) With neat sketches explain the working of 4-stroke cycle petrol engine.
2. (a) What are the disadvantages of wet compression?
(b) Explain the desirable properties of refrigerants.
3. (a) Describe how flame cutting is done stating its principle.
(b) What are the temperature factors to be taken into account while selecting the
welding rods? Explain them.
4. (a) Name the different types of lathes and discuss their applications.
(b) Describe with the help of neat sketches the following work holding devices
used in planer:
i. Holding strap
ii. End stop pin.
5. (a) Effect of the following on Power Shovels out put
i. Management conditions
ii. Size of holding units.
(b) What are the applications of Screw Conveyors?
1. Explain the building of the emf in a shunt generator.
2. From the fundamental, derive the expression for the Torque.
3. Explain the phasor diagram of a transformer ‘on load’ with lagging pf .
4. From the following test results determine the regulation of a 2 KV single phase
alternator delivering a current of 100 A at 0.8 Pf lagging. Test results: full load
current of 100 A is produced on short circuit by a field excitation of 2.5 A. An
emf of 500V is produced on open circuit by the same excitation. The armature
resistance is 0.8 ohms.
5. (a) Explain the advantages and disadvantages of Moving Iron instruments.
(b) Explain the working of moving iron attraction type instruments.