(SEM IV) THEORY EXAMINATION 2017-18 MEASUREMENT AND METROLOGY

The B.Tech Measurement and Metrology (RME401) question paper from the 2017–18 IV Semester Theory Examination is a meticulously structured, 70-mark assessment aimed at evaluating a student’s understanding of measurement systems, industrial metrology, sensors, gauges, limits & fits, strain measurement, precision instruments, and temperature/pressure measurement devices. The exam contains conceptual, descriptive, and numerical questions distributed across three major sections meant to test both theoretical knowledge and application-based problem-solving. 

MEASUREMENT-AND-METROLOGY-RME401

SECTION A – Basic Concepts (Short Answer Questions, 14 Marks)

This section consists of 7 short questions, each carrying 2 marks, to assess foundational understanding of measurement science. Students answer definitions and basic distinctions related to:

Metrology and its purpose in engineering          Sensitivity of measuring instruments

Functions of sensors                                              Temperature-measuring instruments (thermocouples, RTDs, pyrometers, etc.)

Zero error in instruments                                        Difference between sensor and transducer

Range vs. span in instruments

This section ensures students are comfortable with the core vocabulary and principles of metrology. 

SECTION B – Intermediate Descriptive Questions (Any 3 × 7 = 21 Marks)

This section contains deeper, explanation-based questions covering:

1. Generalized Measurement System

Students must explain the block diagram, including elements such as:

Primary sensing element                        Variable conversion element

Signal conditioning                                Data presentation

With relevant examples like pressure measurement or temperature measurement. 

2. Types of Sensors

Classification of sensors based on physical property (thermal, mechanical, optical, etc.), with:

Applications                   Advantages                 Limitations

3. Low-pressure Measuring Devices & McLeod Gauge

Students list low-pressure devices (e.g., Pirani gauge, ionization gauge) and explain McLeod gauge working principle clearly.

4. Interferometry

A popular question explaining:

Working principle (light interference)

Applications: surface flatness, gauge block calibration, etc.

5. Coordinate Measuring Machine (CMM)

Construction, types (bridge type, cantilever type, gantry type), applications, & advantages with a neat sketch.

These questions test clarity of thought, diagrammatic accuracy, and conceptual depth. 

SECTION C – Advanced Problems, Instruments & Numerical Questions (5 × 7 Marks)

This section contains analytical, design-based, and numerical questions, each with internal choice.

Q3 – Limits, Fits, Gauges & Tolerances

Taylor’s principle of gauge design

Numerical problem:

Determine dimensions for 30H7/h9 fit, allowance, and maximum clearance

OR: Short notes on:

Limits, fits, tolerances

Comparators (mechanical, optical, electrical)
 

Q4 – Specialized Instruments

Topics include:

Johansson’s Microkrator (precision measurement)

Accelerometer

Strain rosettes
Or explanation of optical pyrometer with construction, working, and industrial significance.
 

Q5 – Autocollimator & System of Fits

Constructional details & usage of autocollimator for measuring:

Straightness

Flatness

Roundness

Or explanation with sketches of:

Hole basis system

Shaft basis system
 

MEASUREMENT-AND-METROLOGY-RME401

Q6 – Strain Gauges & Measurement Devices

Classification of strain gauges (wire, foil, semiconductor)

Working of Wheatstone bridge in balanced/unbalanced conditions

OR notes on:

Stroboscope

Thermistor

Seismic instruments

Q7 – Numerical Problems in Temperature & Strain Measurement

Includes engineering numerical calculations such as:

1. Platinum Resistance Thermometer

Find resistance at given temperature

Find temperature for given resistance (using α = 0.004 Ω/Ω°C)

2. Strain Gauge Numerical

Given:

Gauge length

Cross-sectional area

Young’s modulus

Change in resistance
Calculate:

Change in length

Applied force

These numericals assess applied mathematical understanding in metrology contexts.
 

OVERALL ESSENCE OF THE PAPER

This question paper thoroughly evaluates:
Understanding of sensors, transducers & gauges
Precision measurement techniques
Industrial metrology (fits, tolerances, limits)
Coordinate measuring systems (CMM)
Interferometry & optical devices
Pressure/temperature measurement systems
Strain measurement & Wheatstone bridge
Numerical problem-solving in measurement science

It serves as an excellent resource for engineering students preparing for metrology-focused examinations and practical industrial applications.