155. Which of the following methods is not concerned with surface finish measurement
A.Spectrophotometry method
B.Ultrasonic method
C.Field emission method
D.Critical angle of attack method

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156. A spirit level is required to have 2 mm of bubble movement of 2" inclination. The
A.Radius of tube should be around
B.(d) 120 m
C.(b) 20 mm
D.(c) 80m

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157. The only natural material producing a spectral line (6440? A red) almost completely symmetrical is
A.Cadmium
B.Mercury
C.Krypton
D.Helium

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158. A photo-electric device in which the resistance of the metal changes directly, proportional to the light striking on it, is known as
A.Photo-cell
B.Photo-emission cell
C.Photo-voltaic cell
D.Photo conductive cell

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159. Universal surface gauge is used for
A.Checking straightness
B.Checking flatness
C.Checking parallelism
D.Layout work and inspection

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160. Which of the following is not the correct method of specifying numerical value of surface roughness mean line
A.Centre-line average (CLA) value
B.Mean-line and envelop line systems
C.R.m.s value
D.Peak-to-valley height

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161. According to Taylor's Principle, No Go gauge checks
A.Only one feature at a time
B.Only important dimensions at a time
C.All the dimensions at a time
D.Only the related 'dimensions at a time

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