Name of the College : Noorul Islam College of Engineering
University : Anna University
Degree : B.E
Department : Mechanical Engineering
Subject Code/Name : ME 1304 – Engineering Metrology & Measurement
Year : 3rd
Semester : 5th
Document Type : Question Bank
Website : niceindia.com
Download Model/Sample Question Paper :https://www.pdfquestion.in/uploads/ni…ASUREMENTS.pdf
Engineering Metrology & Measurement Question Paper
Unit I- Concept Of Measurment :
1.Differentiate accuracy and Uncertainty with example :
Accuracy – Closeness to the true value.
Example :
Measuring accuracy is ± 0.02mm for diameter 25mm. Here the measurement true values lie between 24.98 to25.02 mm Uncertanity about the true value = ± 0.02mm
Related : Dasari Jhansi Rani Institute Of Engineering And Technology RR220205 Electro Mechanics-II B.Tech Question Paper : www.pdfquestion.in/3033.html
2. Differentiate between precision and accuracy :
Accuracy – The maximum amount by which the result differ from true value.
Precision – Degree of repetitiveness. If an instrument is not precise it will give different results for the same dimension for the repeated readings.
3. Differentiate between sensitivity and range with suitable example :
Example :
A Instrument have a scale reading of 0.01mm to 100mm. Here, the sensitivity of the instrument is 0.0lmm i.e. the minimum value in the scale by which the instrument can read. The range is 0.01 to 100mm i.e. the minimum to maximum value by which the instrument can read.
4. Deflne system error and correction :
Error : The deviation between the results of measured value to the actual value.
Correction : The numerical value which should be added to the measured value to get the correct result.
5. Define : Measurand:
Measurand is the physical quantity or property like length, diameter, and angle to be measured.
6. Define : Deterministic Metrology:
The metrology in which part measurement is replaced by process measurement. The new techniques such as 3D error compensation by CNC systems are applied.
7.Define over damped and under damped systenL :
Over damped – The final indication of measurement ii approached exponentially from one side.
Under damped – The pointer approach the position corresponding to final reading and makes a number of oscillations around it.
8.Give any four methods of measurement :
1. Direct method.
2. Indirect method.
3. Comparison method.
4. Coincidence method.
9. Give classification of measuring instruments :
1. Angle measuring Instruments.
2. Length measuring Instruments.
3. Instruments for surface finish.
4. Instruments for deviations.
10 .Define True size :
True size is Theoretical size of a dimension
11. Define Actual size :
Actual size = Size obtained through measurement with permissible error.
12. What is Hysteresis :
All the energy put into the stressed component when loaded is not recovered upon unloading. So, the output of measurement partially depends on input called hoteresis.
13.What is Range of measurement :
The physical variables that are measured between two values. One is the higher calibration value H , and the other is Lower value L, The difference between H, and L, is called range.
14.Define Span :
The algebraic difference between higher calibration values to lower calibration value.
Example :
In a measurement of temperature higher value is 200*C and lower value is 1500C means span = 200 – 150 = 50’C
15. What is Resolution :
The minimum value of the input signal is required to cause an appreciable change in the output known as resolution.
16. What is Scale interval :
It is the difference between two successive scale marks in units.
17.What is Response time :
The time at which the instrument begins its response for a change measured quantity.
18. Define Repeatability :
The ability of the measuring instrument to repeat the same results g the act measurements for the same quantity is known as atability.
19. Explain the term magniftication :
It means the magnitude of output signal of measuring instrument times increases to make it more readable.
20. Classify the Absolute error :
The absolute error is classified into
1. True absolute error
2. Apparent absolute error