Quality Control and Metrology MCQs 2026

Preventive action aims to

1. A eliminate potential nonconformity before occurrence ✓
2. B react only after customer complaint always ✓
3. C only increase sampling defects ✓
4. D only ignore trends ✓

Pakistan Standards and Quality Control Authority (PSQCA) develops

1. A only cricket rules ✓
2. B Pakistan Standards (PS) for products ✓
3. C only motorway speed limits exclusively ✓
4. D only university degrees exclusively ✓

GD&T position tolerance zone for hole is typically

1. A only flat zone parallel to surface always for position ✓
2. B cylindrical zone where axis must lie ✓
3. C only colour band ✓
4. D only hardness zone ✓

MMC bonus tolerance in GD&T allows

1. A less tolerance always ✓
2. B additional tolerance as feature departs from maximum material condition ✓
3. C zero tolerance always ✓
4. D only roughness increase ✓

First article inspection (FAI) verifies

1. A initial production part against drawing before full run ✓
2. B only last part of million without first ✓
3. C only packaging labels ✓
4. D only marketing brochure ✓

Poka-yoke in quality prevents

1. A defects by increasing inspection only after damage ✓
2. B only increasing batch size ✓
3. C defects by error-proofing the process ✓
4. D only hiding defects ✓

Root cause analysis tools include

1. A only random guessing ✓
2. B only ignoring data ✓
3. C only increasing scrap ✓
4. D 5 Whys and fishbone (Ishikawa) diagram ✓

Fishbone diagram categories often include

1. A only profit, loss, tax, audit ✓
2. B only cricket, hockey ✓
3. C only latitude, longitude ✓
4. D Man, Machine, Material, Method, Measurement, Environment ✓

Gauge R&R study evaluates

1. A only part weight shipping ✓
2. B only tool rake angle production ✓
3. C repeatability and reproducibility of measurement system ✓
4. D only furnace temperature process without gauge ✓

Ring gauge checks

1. A external shaft diameter ✓
2. B only internal thread only ✓
3. C only flatness of plate only ✓
4. D only hardness ✓

Plug gauge checks

1. A only shaft OD always ✓
2. B hole diameter ✓
3. C only thread pitch only without diameter ✓
4. D only surface finish only ✓

GO and NO-GO gauges check

1. A only chemical composition quantitatively ✓
2. B whether feature is within tolerance limits quickly ✓
3. C only colour shade ✓
4. D only sound frequency ✓

Gauge blocks (slip gauges) are used for

1. A calibrating and setting dimensional standards ✓
2. B only cutting speed on lathe ✓
3. C only boiler pressure ✓
4. D only air humidity ✓

Dial indicator measures

1. A only chemical pH ✓
2. B only electrical power kW ✓
3. C small linear displacements amplified on dial ✓
4. D only mass in tonnes only ✓

Micrometer screw gauge measures using

1. A only laser triangulation always ✓
2. B only magnetic flux ✓
3. C only water displacement ✓
4. D precision screw and thimble scale ✓

Least count of instrument is

1. A maximum range only ✓
2. B only parallax error ✓
3. C only calibration certificate number ✓
4. D smallest measurable increment ✓

Vernier caliper can measure

1. A only surface roughness Ra ✓
2. B only hardness HRC ✓
3. C external, internal dimensions and depths with 0.02 or 0.05 mm resolution typically ✓
4. D only temperature ✓

Precision of measurement means

1. A repeatability or consistency of repeated measurements ✓
2. B closeness to true value always same as accuracy term ✓
3. C only instrument colour ✓
4. D only operator height ✓

Accuracy of measurement means

1. A repeatability only without reference ✓
2. B closeness to true or accepted reference value ✓
3. C only speed of measurement ✓
4. D only instrument cost ✓

Metrology is the science of

1. A only metal casting ✓
2. B measurement and its application to standards ✓
3. C only motor racing ✓
4. D only meteorology weather exclusively ✓

Quality control in manufacturing aims to

1. A ensure products meet specifications and customer requirements ✓
2. B maximize defect rate ✓
3. C eliminate all measurement ✓
4. D ignore tolerances ✓

Repeatability in GRR is variation when

1. A same operator measures same parts repeatedly ✓
2. B different operators only ✓
3. C different parts only ✓
4. D different instruments only across plants ✓

Reproducibility in GRR is variation when

1. A same operator only ✓
2. B different operators measure same parts ✓
3. C only environmental music ✓
4. D only paint colour ✓

Unilateral tolerance on shaft maximum diameter example

1. A equal bilateral ±0.5 always only ✓
2. B 25 mm maximum with no minimum stated beyond zero practically ✓
3. C only angle tolerance ✓
4. D only hardness range ✓

Thermal expansion affects precision measurement; compensation uses

1. A coefficient of expansion and temperature difference ✓
2. B only paint colour ✓
3. C only operator gloves ✓
4. D only air pressure without temperature ✓

Cosine error in measurement occurs when

1. A only random vibration ✓
2. B only temperature zero ✓
3. C measuring axis not parallel to feature being measured ✓
4. D only humidity 100% ✓

Abbe principle recommends

1. A maximizing offset between axes ✓
2. B ignoring alignment ✓
3. C only using flexible tape for precision ✓
4. D measuring axis aligned with standard axis to minimize cosine error ✓

Parallax error in scale reading is reduced by

1. A reading at glancing angle deliberately ✓
2. B using only mirror without alignment ✓
3. C ignoring scale ✓
4. D aligning eye perpendicular to scale ✓

Traceability in metrology chain links

1. A only factory floor without reference ✓
2. B only random number ✓
3. C measurements to national or international primary standards ✓
4. D only operator memory ✓

Calibration of instrument means

1. A comparing and adjusting to traceable standard ✓
2. B only cleaning exterior ✓
3. C only painting scale ✓
4. D only increasing range arbitrarily ✓

ISO 9001 addresses

1. A only environmental emissions only ISO 14001 ✓
2. B quality management system requirements ✓
3. C only occupational health ISO 45001 ✓
4. D only welding rod chemistry only ✓

AQL (Acceptable Quality Level) is

1. A always zero defects required in all sampling without economics ✓
2. B maximum percent defective considered acceptable in sampling ✓
3. C only machine uptime ✓
4. D only tool rake angle ✓

Acceptance sampling inspects

1. A sample of lot to decide accept or reject batch ✓
2. B every atom in universe ✓
3. C only supplier logo ✓
4. D only packaging colour without parts ✓

Six Sigma quality level corresponds roughly to

1. A 50% defects ✓
2. B 100% defects ✓
3. C 3.4 DPMO long-term ✓
4. D zero measurement ✓

Process capability index Cpk measures

1. A only tool wear VB only ✓
2. B only machine colour ✓
3. C only shipping weight ✓
4. D how well process fits specification considering centering ✓

Out-of-control signal on X-bar chart may show

1. A only points exactly on mean always ✓
2. B only within 1σ always natural only without rules ✓
3. C only labels change ✓
4. D points outside control limits or non-random patterns ✓

Control chart upper control limit typically set at

1. A mean only without spread ✓
2. B zero always ✓
3. C mean plus three sigma for variables chart ✓
4. D mean minus 3σ for UCL wrong ✓

Statistical Process Control (SPC) uses

1. A control charts to monitor process variation ✓
2. B only final destructive test without data history ✓
3. C only operator opinion without data ✓
4. D only inventory ABC ✓

CMM provides

1. A only 1D weight only ✓
2. B automated 3D coordinate measurement of part features ✓
3. C only chemical assay ✓
4. D only sound level dB ✓

Optical flat checks

1. A only thread pitch only ✓
2. B surface flatness by interference fringes ✓
3. C only tensile strength ✓
4. D only colour hue artistic ✓

Sine bar with slip gauges measures

1. A angles accurately using trigonometry ✓
2. B only hardness ✓
3. C only current amperes ✓
4. D only flow rate m³/s without trigonometry ✓

Fit symbol H7/g6 indicates

1. A clearance fit with hole basis system ✓
2. B interference only ✓
3. C only shaft basis without hole H ✓
4. D only welding symbol ✓

Comparator magnifies

1. A only electrical voltage 1000x without mechanical part ✓
2. B only mass 1000x ✓
3. C small dimensional differences for inspection ✓
4. D only temperature without sensor ✓

Rougher surface generally has

1. A lower Ra always ✓
2. B zero Ra always ✓
3. C Ra independent of profile ✓
4. D higher Ra value ✓

Profile projector (shadowgraph) magnifies

1. A only internal chemistry ✓
2. B only magnetic field ✓
3. C silhouette for thread and form inspection ✓
4. D only thermal conductivity ✓

Surface roughness Ra is

1. A peak-to-valley Rmax always same symbol ✓
2. B hardness number ✓
3. C dimensional tolerance zone ✓
4. D arithmetic average of profile deviations from mean line ✓

Hardness testing in QC may use

1. A only vernier for hardness number ✓
2. B only micrometer for HRC ✓
3. C only dial indicator for HB ✓
4. D Rockwell or Brinell for material verification ✓

Thread gauge ensures

1. A only electrical continuity ✓
2. B only paint thickness ✓
3. C pitch diameter and form within limits ✓
4. D only weight of bolt head only ✓

Nonconforming product control requires

1. A mixing with good parts ✓
2. B shipping without record ✓
3. C only hiding from auditor ✓
4. D identification, segregation and disposition (rework, scrap, use-as-is) ✓

Corrective action differs from correction in that it

1. A only fixes immediate instance without cause analysis ✓
2. B only documents without action ✓
3. C eliminates root cause to prevent recurrence ✓
4. D only increases defect rate ✓