Objective Questions 439
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d:\N-Design\Des22-1.pm5
10. In unilateral tolerance, the limits will be on of the basic size.
11. In bilateral tolerance, the limits are on of the basic size.
12. _____ basis system of fits are normally used.
13. In hole basis system, the lower deviation is _____ for the letter symbol H.
14. Shaft basis system is preferred in _____ industries.
(a) Textile (b) Automobile (c) Aircrafts
15. If the allowance is positive, it results in .
(a) Clearance fit (b) interference fit
16. If the allowance is negative, the fit is _____.
(a) Interference (b) Clearance (c) Transition
17. For shrink fit with a hole of H8, the shaft tolerance is given by _____.
(a) n6 (b) c7 (c) U8
18. A clearance fit is obtained from _____.
(a) H7/n6 (b) H7/g6 (c) H7/m6
19. The fit recommended on shaft for ball bearing mounting is _____.
(a) H7/g6 (b) H7/f6 (c) H7/m6
20. The fundamental deviations are given in _____ units.
21. Fundamental tolerance of a shaft of size 30 mm for grade 6 is _____.
22. Fundamental deviation of shaft of size 18 mm and letter symbol ‘f ’ is _____.
23. Lower deviation of a hole of size 30 H7 is _____.
24. The lower deviation of 30m6 is _____.
25. The upper deviation of 30m6 is _____.
CHAPTER 16
1. Higher the smoothness of the surface, better is the corrosion resistance (True/False).
2. With better surface finish, friction between mating parts is not reduced (True/False).
3. Surface roughness is indicated by _____.
(a) Rt (b) Ra
4. Surface flatness is measured by _____.
(a) Micrometer (b) Feeler guage (c) Optical flat
5. Roughness value Ra is given in _____ units.
6. The Ra value for turning is to .
7. The Ra value for honing is _____.
(a) 0.025 (b) 0.4 (c) 0.015
8. The roughness value for lapping is _____.
(a) 0.012 (b) 0.06 (c) 0.04
9. The roughness value for super finishing is to .
10. The roughness value for forging is to .
11. The roughness grade for 50 μm is _____.
12. The roughness value for grade N2 is _____.
13. Lay indicates the surface finish pattern (True/False).
14. Two triangles indicate .
(a) Fine finish (b) Rough finish
