85. Precision is
A.The repeatability of a measuring process
B.Agreement of the result of a measurement with the true value of the measured quantity
C.The ability of a measuring device to detect small differences in a quantity being measured the ability of an instrument to reproduce same reading under identical conditions
D.(e) error of judgment in reading an observation.

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86. The thickness of oil film at the surface of slip gauges is of the order of
A..005 micron
B..1 micron
C.1 micron
D.10 microns

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87. Pick up the wrong statement. Surface plates are usually made of granite because of following advantages
A.Because of long period of time for relaxing, it is free from built in residual stresses. There is no corrosion effect also.
B.It enables the phenomenon of wringing flat surfaces over it.
C.If a tool or workpiece drops accidently over its surface, residual stresses are not induced
D.It simply powders somewhat at the point of impact by falling object

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88. Pick up the wrong statement.
A.Error is the disagreement between the result of measurement and actual value.
B.Random error are regularly repetitive in nature and result from improper conditions or procedures that are consistant in action
C.Parasitic error results from incorrect execution of measurement.
D.Uncertainty of measurement represents the dispersion of the result of measurement defmed by the limits of the error.

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89. Which one of the following instruments is the most accurate
A.Steel scale
B.Optical projector.
C.Vernier caliper
D.Vernier dial gauge

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90. In the case of high precision surface plates of diameter upto 200 mm, the working surface should lie between two parallel planes, whose maximum distance apart is
A.0.005 mm
B.0.0005 mm
C.0.05 mm
D.0.5 mm

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91. Which of the following is not the accessory of slip gauges :
A.Scribing and centre points
B.Measuring jaws
C.Holder
D.Calipers

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