MORE IN Mechanical Measurement and Metrology
VTU Mechanical Engineering (Semester 4)
Mechanical Measurement and Metrology
December 2014
Total marks: --
Total time: --
INSTRUCTIONS
(1) Assume appropriate data and state your reasons
(2) Marks are given to the right of every question
(3) Draw neat diagrams wherever necessary

1 (a) Define metrology. what are the objectives of metrology.
5 M
1 (b) Explain "Imperial standard yard" and "International prototype meter", with neat sketches.
10 M
1 (c) A calibrated meter end bar has an actual length of 1000.0002 mm. It is used in calibration of two bars A and B, each having a basic length of 500 mm. When compared with the meter bar LA+ LB was found to be shorter by 0.0003 mm. In comparing A and B, it was found thatA was 0.0004 mm longer than B. Find the actual length of A and B.
5 M

2 (a) Differentiate : i) unilateral and bilateral tolerances ii) clearance fit and interference fit.
6 M
2 (b) Determine the dimensions of shaft and hole for a fit 30 H⊂7f ⊂ 8. The given data are: $i=0.45 \sqrt[3]{D}+0.001D$ microns. Fundamental deviation for f shaft is -5.5D ⊃ 0.41 at microns, 30 mm falls in the diameter step of 18 and 30. Tolerance grade for IT⊂ 7 and IT⊂8 are 16i and 25i respectively. Also design plug gauge to check the above hole. Take wear allowance as 10% of the gauge tolerance.
10 M
2 (c) Explain : i) Shaft basis system ii)Hole basis system.
4 M

3 (a) With a neat sketch, explain the construction and working of Johannson Mikrokator comparator
8 M
3 (b) Explain with a neat sketch, the working of Solex pneumatic comparator. What are its advantages?
8 M
3 (c) Explain the principle of sine bar.
4 M

4 (a) With a neat sketch, explain the working principle of an autocollimator.
6 M
4 (b) Define "Effective diameter". Explain the 3-wire method of finding the effective diameter of screw threads.
8 M
4 (c) Explain with a sketch, how the chordal thickness is measured by using gear tooth vernier calliper.l
6 M

5 (a) Define measurement. With a block diagram,explain the generalized measurement system explain the with a suitable example.
8 M
5 (b) Define the following terms : i) precision ii) hysteresis iii) sensitivity.
6 M
5 (c) Explain the principle of capacitive type electrical transducer. With a skech explain any one type of capacitive transducer.
6 M

6 (a) Explain th inherent problems present in mechanical modifying system.
6 M
6 (b) With a block diagram, explain the general telemetering system.
6 M
6 (c) Explain with neat sketches : i) stylus type oscillograph ii) x - y ? plotter.
8 M

7 (a) Sketch and explain the analytical balance (equal arm balance).
8 M
7 (c) Describe the working principle of pirani gauge with a sketch.
6 M
7(b) Explain how the torque is measured using Prony brake dynamometer. What are its disadvantages?
6 M

8 (a) State the laws of thermocouples.
4 M
8 (b) Explain the construction and working of optical pyrometer.
8 M
8 (c) Define gauge factor. Explain the wheat stone bridge arrangement for stain measurement.
8 M

More question papers from Mechanical Measurement and Metrology