1.Define Metrology

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It is defined as the science of measurement, embracing both experimental and theoretical determinations at any level of uncertainty in any field of science and technology.

2. Define Uncertainty of Measurement.

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It is defined as a “parameter, associated with the result of a measurement, that characterizes the dispersion of the values that could reasonably be attributed to the measurand.

3. Define Legal Metrology.

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Legal Metrology applies to any application of metrology that is subjected to national laws or regulations.
The main objective is to maintain uniformity of measurement in a particular country.

4.Define Inspection

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Inspection is defined as a procedure in which a part or product characteristic, such as a dimension, is examined to determine whether it conforms to the design specification

5.What do you mean traceability of the standards and Calibration of Measuring Instruments.

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The process of validation of the measurements to ascertain whether the given physical quantity conforms to the original/national standard of measurement is known as traceability of the standard.
Calibration is the procedure used to establish a relationship between the values of the quantities indicated by the measuring instrument and the corresponding values realized by standards under specified conditions.

6.State types of errors in measurement.

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1Gross errors
(i)Using a wrong instrument.
(ii)Faulty setting of the instrument.
(iii) Mistake in reading or recording observation.
(iv) Mistake in applying a correction.
(v)Wrong computation and procedure or mistake in computation
2. Systematic errors
(1) Instrument errors
(ill) Environment errors
(ili) Observational errors
(iv) Operational errors
(v) System interaction errors
3. Random errors
(i) Friction and stickiness of surfaces.
(ii)Vibrations.
(iii) Large tolerances between the mating parts.
(iv) Hysteresis.
(v) Backlash in instruments.
(vi) Variation in supply power.
(vi) Elastic deformation of parts.

7. ) Define interchangeability.

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It is defined as the quality of being capable of exchange or interchange. Interchangeability or interchangeability is very important in every area of modern life. If a worn out or broken part is replaced by another new part and performs the same function as the old part, the two parts will be mutually interchangeable and this property will be called interchangeability.

8.What are the different types of Fits?

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Clearance Fit
The diameter of the shaft is smaller than the diameter of the hole. There is a clearance between the shaft and the hole. Hence the shaft can easily slide into the hole. In clearance fit the difference between the maximum size of the hole and the minimum size of the shaft is known as the Maximum clearance and the difference between the minimum size of the hole and the maximum size of the shaft is known as the Minimum clearance.
Interference Fit
The diameter of the shaft is larger than the hole diameter. There will be the intersection of two mating components that will be occurred. Hence the shaft will need additional force to fit into the hole. In Interference fit the difference between the maximum size of the shaft and the minimum size of the hole is known as the Maximum Interference and the difference between the minimum size of the shaft and the maximum size of the hole is known as the Minimum Interference.
Transition Fit
The tolerance zones of the shaft and the hole will be overlapped between the interference and clearance fits. See the following schematic representation of the transition fit. In transition fit, the tolerance zones are overlapped

9.State taylor's principle of gauge design?

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This principle states that the GO gauge should be designed in such a way that it will check the maximum material condition of as many dimensions as possible where as a NO-GO gauge should inspect the minimum material condition of one dimension only at a time as shown.

10.What are the types of limit gauges?

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I. Go and No-Go / Plug
II. Ring
III. Snap