15. Which of the following errors are inevitable in the measuring system and it would be vainflul exercise to avoid them
A.Systematic errors
B.Random errors
C.Calibration errors
D.Environmental errors

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16. Which of the following instruments is most accurate
A.Vertical caliper
B.Manometric screw gauge
C.Optical projector
D.Mechanical comparator

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17. Which of the following refers to parasitic error.
A.Error, often gross, which results from incorrect execution of measurement
B.Algebraic difference between the results of measurement and the value of comparison
C.Error which varies in an unpredictable manner in absolute value and in sign when a large number of measurements of the same value of a quantity are made under practically identical conditions.
D.Disagreement between the result of measurement and the value of the quantity measured

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18. Which of the following characterises the dispersion of the results obtained in a series of measurements of the same value of a quantity measured
A.Absolute error
B.Relative error
C.Root mean square deviation
D.Uncertainty of measurement

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19. A surface gauge is used for
A.Levelling the surface plate
B.Checking the surface fmish
C.Laying out the work accurately
D.Finding the depth of the surface

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20. Parasitic error is caused due to
A.Improper use of measuring instrument
B.Wrong design of instrument
C.Changes in ambient conditions
D.Errors in computation

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21. A feeler gauge is used to check
A.Radius
B.Thickness of clearance.
C.Surface roughness
D.Unsymmetrical shape

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