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UPMSP Intermediate Technical Drawing study materials
UPMSP Intermediate Technical Drawing study resources

UPMSP Intermediate Technical Drawing practice questions

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Question 1Drawing Instruments, Materials and Basic Conventions

In technical drawing, which pencil grade is normally selected for drawing the final visible outlines on a finished sheet?

  1. 2H or H Correct answer.
  2. 4B or 6B
  3. 6H or 7H
  4. HB or B

Explanation

Visible outlines must be dark and crisp yet still fine, so a medium-hard grade such as H or 2H is standard. Softer grades smudge easily under the hand and lose line sharpness, while very hard grades indent and score the paper.

Question 2Drawing Instruments, Materials and Basic Conventions

A drawing sheet is described as A3 size. Which set of trimmed dimensions corresponds to that sheet under the ISO A series?

  1. 594 mm × 841 mm
  2. 210 mm × 297 mm
  3. 420 mm × 594 mm Correct answer.
  4. 297 mm × 420 mm

Explanation

The A series halves each area at every step, so A0 is 841 mm × 1189 mm and each following size halves the longer side. A3 is therefore 420 mm × 594 mm, exactly half of A2.

Question 3Drawing Instruments, Materials and Basic Conventions

Which instrument is used to draw a circle of radius 65 mm accurately with a pencil lead?

  1. Protractor
  2. Bow compass Correct answer.
  3. French curve
  4. Set square

Explanation

A bow compass is a small spring-bow instrument designed for circles of small and moderate radius, and it holds a short lead that keeps the point steady. French curves, set squares and protractors cannot sweep an arc about a centre point.

Question 4Drawing Instruments, Materials and Basic Conventions

What does the abbreviation 'R' placed before a dimension value, as in R25, indicate on a technical drawing?

  1. The surface is to be rough machined
  2. The dimension is a radius Correct answer.
  3. The dimension is repeated on another view
  4. The dimension is a reference dimension

Explanation

The prefix R is the standard symbol for radius, so R25 means an arc or fillet of 25 mm radius. Reference dimensions are shown in brackets, and machining notes are given as surface texture symbols, not as letter prefixes.

Question 5Drawing Instruments, Materials and Basic Conventions

Which line type is drawn as a thin chain line with long dashes and short gaps in a technical drawing?

  1. Cutting plane line
  2. Hidden detail line
  3. Visible outline
  4. Centre line Correct answer.

Explanation

Centre lines, which mark axes of symmetry and centres of circles, are drawn as thin chain lines of alternating long dashes and short gaps. Hidden edges use short evenly spaced dashes, and cutting planes use a heavy chain with thick ends.

Question 6Drawing Instruments, Materials and Basic Conventions

A draughtsman must draw a line at exactly 75° to a horizontal reference using only a T-square and a 45° set square. Which practical method gives that angle?

  1. Bisect a 60° angle twice with the compass
  2. Rotate the T-square blade by 15° from the board edge
  3. Draw 45° first, then add 30° by combining with the 30-60-90 set square Correct answer.
  4. Use the 45° set square alone and estimate the remainder

Explanation

Set squares give fixed angles, and 75° is obtained by combining the 45° square with the 30° angle of the 30-60-90 square. Angles that are not multiples of 15° must be constructed with compass bisection, but 75° is a standard combination.

Question 7Drawing Instruments, Materials and Basic Conventions

On a drawing, a feature is dimensioned as 40 ± 0.2. What is the permissible range of the actual size?

  1. 39.8 mm to 40.0 mm
  2. 39.6 mm to 40.4 mm
  3. 39.8 mm to 40.2 mm Correct answer.
  4. 40.0 mm to 40.2 mm

Explanation

The tolerance of ±0.2 mm is added to and subtracted from the nominal size, giving a maximum of 40.2 mm and a minimum of 39.8 mm. Both limits must be respected for the part to be accepted.

Question 8Drawing Instruments, Materials and Basic Conventions

A drawing is prepared at a scale of 1:5. A line on the drawing measures 36 mm. What is the corresponding real length of the object?

  1. 360 mm
  2. 180 mm Correct answer.
  3. 72 mm
  4. 7.2 mm

Explanation

A scale of 1:5 means one unit on the drawing represents five units on the object, so the drawing length is multiplied by 5. Thus 36 mm × 5 = 180 mm, which is a reduction scale.

Question 9Drawing Instruments, Materials and Basic Conventions

Which statement correctly describes the purpose of a border and title block on a drawing sheet?

  1. The border marks the folding line and the title block gives the bill of materials
  2. The border fixes the scale and the title block lists the tolerances only
  3. The border shows the cutting plane and the title block carries the section hatching
  4. The border frames the drawing area and the title block records identification and drawing data Correct answer.

Explanation

The border defines the working area inside the trimmed edges and protects the drawing from damage, while the title block carries the drawing number, title, scale, date, and approval details. Together they make the sheet identifiable and traceable.

Question 10Drawing Instruments, Materials and Basic Conventions

A dimension line must be drawn for a small gap of 6 mm between two visible lines. What is the accepted drafting practice for the arrowheads?

  1. Draw the arrowheads inside and allow them to overlap each other
  2. Omit the dimension line entirely and write the value on the extension line
  3. Place the arrowheads outside the extension lines and extend the dimension line Correct answer.
  4. Use a leader pointing to the gap with the value written above it

Explanation

When the space between extension lines is too small for the arrowheads, they are placed outside the extension lines and the dimension line is extended beyond them. The dimension value is written between the extension lines or above the extended line as space allows.

Question 11Drawing Instruments, Materials and Basic Conventions

Which statement about hidden detail lines is correct?

  1. They are drawn as chain lines to indicate axes of symmetry
  2. They are always drawn in red to distinguish them from visible outlines
  3. They are thin short dashes and are omitted where a visible line would coincide with them Correct answer.
  4. They are drawn as thick continuous lines to show internal features

Explanation

Hidden edges are shown by thin, short, evenly spaced dashes, and drafting convention requires that where a hidden line coincides with a visible line, the visible line takes precedence. This keeps the drawing readable and avoids duplication.

Question 12Drawing Instruments, Materials and Basic Conventions

A hole is dimensioned as Ø20 with a note '2 HOLES'. Why is a leader with the diameter symbol used here instead of two separate dimension lines?

  1. A leader with a symbol dimensions a feature once and the note gives the quantity, avoiding repeated dimensions Correct answer.
  2. The note replaces the diameter symbol so the leader can be omitted
  3. Leaders are used because the hole is circular and dimension lines cannot touch circles
  4. Two dimension lines would change the tolerance of the holes

Explanation

When identical features repeat, standard practice is to dimension one of them and state the number of places in a note, using a leader with the diameter symbol. This avoids clutter and prevents conflicting values on the same drawing.

Question 13Drawing Instruments, Materials and Basic Conventions

During drawing, a compass lead is sharpened to a chisel edge on one side. What is the reason for this?

  1. It prevents the lead from breaking when the compass is closed
  2. It allows the compass to draw both thick and thin lines without adjustment
  3. It keeps the line width uniform as the compass rotates about the centre Correct answer.
  4. It makes the compass usable as a divider for transferring lengths

Explanation

A compass rotates about its needle point, so the lead contacts the paper at a changing angle. A chisel-shaped point keeps the contact edge aligned with the direction of travel, producing an even line width around the arc.

Question 14Drawing Instruments, Materials and Basic Conventions

A drawing is to be reduced photographically by a factor of 4 and must still show lines of at least 0.25 mm on the final print. What is the minimum line width on the original sheet?

  1. 0.0625 mm
  2. 4.0 mm
  3. 1.0 mm Correct answer.
  4. 0.5 mm

Explanation

Reduction shrinks every line by the same factor, so the original width must be the required final width multiplied by the reduction factor. Thus 0.25 mm × 4 = 1.0 mm on the original sheet.

Question 15Drawing Instruments, Materials and Basic Conventions

A dimension of 50 mm is required on an object drawn at scale 1:2, and the drawing is later reproduced at 200% of its original size. What value must be printed in the dimension text on the drawing?

  1. 25
  2. 200
  3. 100
  4. 50 Correct answer.

Explanation

Dimension text always states the true size of the object, regardless of the drawing scale or any later reproduction. The scale affects only the graphical length of the line, so the value remains 50.

Question 16Drawing Instruments, Materials and Basic Conventions

A draughtsman needs to divide a straight line of 84 mm into seven equal parts using only a scale, compass and set square. Which construction is correct?

  1. Draw an inclined line from one end with seven equal divisions, join the last division to the other end, then draw parallels Correct answer.
  2. Bisect the line three times with the compass to obtain seven parts
  3. Divide 84 mm by seven and mark each 12 mm with the set square alone
  4. Step off 12 mm seven times along the line with the compass

Explanation

The standard construction for dividing a line into equal parts uses an auxiliary inclined line carrying the required number of equal divisions. Joining the last division to the far end of the given line and drawing parallels through the other divisions transfers the equal spacing onto the line.

Question 17Lettering, Dimensioning and Line Work

In a technical drawing sheet, which lettering height is normally recommended for the main title block entries when the drawing is read at normal viewing distance?

  1. 0.7 mm
  2. 2 mm
  3. 1.5 mm
  4. 7 mm Correct answer.

Explanation

Standard drawing practice assigns letter heights according to the importance of the text: titles and drawing numbers use the largest size, usually 7 mm, while notes use 3.5 to 5 mm and subscripts use about 2.5 mm. A 7 mm height keeps the title legible when the sheet is viewed from a distance.

Question 18Lettering, Dimensioning and Line Work

Which type of line is drawn as a thick continuous line to represent the visible outline of an object?

  1. Chain thin line
  2. Continuous thick line Correct answer.
  3. Dashed thin line
  4. Continuous thin line

Explanation

Visible edges and outlines are always shown by a continuous thick line, which is the heaviest line on the drawing. Its thickness is roughly three times that of a thin line and it must be uniformly dark along its full length.

Question 19Lettering, Dimensioning and Line Work

A chain thin line with long dashes and short gaps is most appropriate for which drawing feature?

  1. The dimension line carrying an arrowhead
  2. The projection line joining two views
  3. The hidden edge of a drilled cavity
  4. The centre line of a symmetrical hole Correct answer.

Explanation

Centre lines, axes of symmetry and pitch circles are drawn with a thin chain line, i.e. long dashes separated by short gaps. Such lines extend a little beyond the feature they locate so that the centre is clearly established.

Question 20Lettering, Dimensioning and Line Work

What does the abbreviation R placed before a numerical value in a dimension indicate?

  1. The surface is to be rough machined
  2. The dimension is a radius Correct answer.
  3. The dimension is a reference size
  4. The dimension is a diameter

Explanation

The prefix R states that the value which follows is the radius of an arc or circle, and it is written before the number without a space. A radius dimension needs only one arrowhead, pointing at the arc being dimensioned.

Question 21Lettering, Dimensioning and Line Work

Which pencil grade is the usual choice for drawing the thick visible outlines on a finished technical drawing?

  1. H
  2. 2H
  3. 4H
  4. HB Correct answer.

Explanation

HB is a medium grade that gives a firm, dark and easily reproducible line, so it suits final outlines and lettering. Harder grades such as H and 2H give faint lines that are difficult to print clearly.

Question 22Lettering, Dimensioning and Line Work

A dimension value of 40 mm is to be placed inside a narrow gap where there is not enough room for the figures between the arrowheads. What is the accepted practice?

  1. Write the figures on the extension lines outside the arrowheads Correct answer.
  2. Write the figures above the dimension line and add a leader pointing to the gap
  3. Place the figures inside the gap at a reduced letter height
  4. Omit the dimension and rely on the scale of the drawing

Explanation

When space between arrowheads is insufficient, the arrowheads are placed outside the extension lines pointing inwards and the value is written between the outward-projecting extension lines. The dimension line itself remains continuous, so the value is never lost.

Question 23Lettering, Dimensioning and Line Work

Which statement about arrowheads used to terminate dimension lines is correct?

  1. They should be about three times as long as they are wide Correct answer.
  2. They should be replaced by small crosses in all cases
  3. They should be drawn as filled circles at the line ends
  4. They should be about five times as long as they are wide

Explanation

A standard arrowhead is a slender triangle whose length is roughly three times its width, and it touches the extension line or the feature it terminates at. Uniform arrowheads throughout a sheet are a mark of careful draughting.

Question 24Lettering, Dimensioning and Line Work

A drawing made at a scale of 1:2 means which of the following?

  1. The drawing is enlarged to twice the object size
  2. Two units on the drawing represent one unit on the object
  3. One unit on the drawing represents two units on the object Correct answer.
  4. The drawing is half the size of the A3 sheet

Explanation

In a scale of 1:2 the first figure refers to the drawing and the second to the object, so every drawn length is half the true length. Reducing scales are used when the object is too large to be drawn full size.

Question 25Lettering, Dimensioning and Line Work

Which guideline applies to the direction of lettering on a technical drawing sheet?

  1. Lettering should follow the direction of each dimension line
  2. Lettering should always be slanted at 75 degrees to the horizontal
  3. Lettering should read from the top or the left-hand edge of the sheet
  4. Lettering should read from the bottom or the right-hand edge of the sheet Correct answer.

Explanation

All text on a drawing must be readable from the bottom edge or from the right-hand edge of the sheet when the drawing is in its normal position. This rule allows the sheet to be read without turning it upside down.

Question 26Lettering, Dimensioning and Line Work

In single-stroke (stroke) lettering, what is the recommended ratio of height to width for capital letters?

  1. About 7:4 Correct answer.
  2. About 1:1
  3. About 3:1
  4. About 1:2

Explanation

Single-stroke capitals are proportioned so that the width is roughly four-sevenths of the height, which gives a slightly narrow, upright appearance. Keeping this ratio constant makes a block of lettering look uniform.

Question 27Lettering, Dimensioning and Line Work

A circular hole of 25 mm diameter must be dimensioned on a drawing. Which notation is correct?

  1. R 25
  2. 25 with a leader to the centre
  3. 25 dia written in words only
  4. 25 Correct answer.

Explanation

A diameter is dimensioned by writing the diameter symbol immediately before the numerical value, with no space between them. The dimension line passes through the centre of the circle and carries arrowheads at both ends.

Question 28Lettering, Dimensioning and Line Work

Which pair of lines must be drawn so that they meet exactly at a corner without overlapping or leaving a gap?

  1. A visible outline and a hidden line at a tangent point
  2. A centre line and a dimension line
  3. A hatching line and an extension line
  4. Two continuous thick outlines forming a corner of the object Correct answer.

Explanation

Where two thick visible outlines meet, they must join precisely at the corner so that the outline reads as a single continuous boundary. Careless joining leaves an overshoot or a gap that is treated as a drawing error.

Question 29Lettering, Dimensioning and Line Work

A dimension is written as 30 with the figures placed above a horizontal dimension line. Where exactly should the figures sit?

  1. Centred below the dimension line, reading from the bottom of the sheet
  2. At the left-hand arrowhead, above the dimension line
  3. Centred above the dimension line, reading from the top of the sheet
  4. Centred above the dimension line, reading from the bottom of the sheet Correct answer.

Explanation

For a horizontal dimension line the value is placed centrally above the line, with a small gap, and is read from the bottom of the sheet. The figures must never be crossed by the dimension line.

Question 30Lettering, Dimensioning and Line Work

Which combination of line thicknesses correctly distinguishes visible outlines from hidden edges on the same drawing?

  1. Visible outlines thick, hidden edges thin and dashed Correct answer.
  2. Visible outlines dashed, hidden edges continuous thin
  3. Visible outlines thin, hidden edges thick
  4. Both visible outlines and hidden edges thick and continuous

Explanation

Visible outlines carry the heaviest continuous line, while hidden edges are drawn as a thin dashed line of the same weight as other thin lines. The contrast in weight lets the eye separate the front contour from features behind it.

Question 31Lettering, Dimensioning and Line Work

On a drawing, a dimension of 50 is enclosed in parentheses as (50). What does this convention signify?

  1. The dimension must be inspected after assembly
  2. The dimension is a reference value given for information only Correct answer.
  3. The dimension has been measured with a vernier calliper
  4. The dimension is the most important size on the drawing

Explanation

Parentheses mark a reference or auxiliary dimension, which is repeated for convenience and is not used for manufacturing or inspection. The controlling dimension appears elsewhere without parentheses.

Question 32Lettering, Dimensioning and Line Work

A draughtsman must show a partially rounded end of a shaft where the arc runs into a straight edge. Which line-treatment rule applies at the point of transition?

  1. A dashed line is drawn across the arc to mark the join
  2. A short gap is left to show that the surfaces are separate
  3. A thin chain line is inserted at the tangent point
  4. The outline continues without a break because the surfaces are tangent Correct answer.

Explanation

When a curved surface blends tangentially into a flat one, no edge exists at the transition, so the outline is drawn as one unbroken line. A line drawn at the tangent point would falsely suggest a sharp corner.

Question 33Geometrical Construction and Scales

In engineering drawing, a scale of 1:50 means that a line 40 mm long on the drawing represents what actual length?

  1. 50 mm
  2. 200 mm
  3. 2000 mm Correct answer.
  4. 500 mm

Explanation

A representative fraction of 1:50 states that one unit on the drawing corresponds to fifty identical units on the object. Multiplying the drawn length 40 mm by 50 gives 2000 mm, which equals 2 m. The ratio is dimensionless, so both quantities are measured in the same unit.

Question 34Geometrical Construction and Scales

A scale in which the drawing is larger than the actual object, such as 5:1, is classified as which type?

  1. Diagonal scale
  2. Enlarging scale Correct answer.
  3. Reducing scale
  4. Full-size scale

Explanation

When the representative fraction is greater than one, each drawn unit represents less than one real unit, so the object is enlarged on paper. Reducing scales have a fraction less than one, and full-size scales equal exactly 1:1. Diagonal scales describe a construction method, not the size relationship.

Question 35Geometrical Construction and Scales

The representative fraction of a scale is defined as which ratio?

  1. Drawing area divided by actual area
  2. Actual area divided by drawing area
  3. Actual length divided by drawing length
  4. Drawing length divided by actual length Correct answer.

Explanation

The representative fraction compares a dimension measured on the drawing with the corresponding real dimension, so it is drawing length over actual length. For a reducing scale this value is less than one. Area ratios are not used to define the representative fraction.

Question 36Geometrical Construction and Scales

A plain scale is to show metres and decimetres with a representative fraction of 1:40. What is the length on the drawing of a main division representing 1 metre?

  1. 4 mm
  2. 25 mm Correct answer.
  3. 2.5 mm
  4. 40 mm

Explanation

One metre equals 1000 mm, and at 1:40 the drawn length is 1000 divided by 40, which is 25 mm. The scale factor is applied by division because the drawing is smaller than the object. Each decimetre would therefore occupy 2.5 mm on the drawing.

Question 37Geometrical Construction and Scales

What is the chief advantage of a diagonal scale over a plain scale?

  1. It is drawn without any division lines
  2. It can measure a third sub-unit by similar triangles Correct answer.
  3. It always gives a full-size drawing
  4. It removes the need for a representative fraction

Explanation

A diagonal scale divides the first main division into ten parts and then uses similar triangles to subdivide one of those parts a second time, giving readings to a second decimal place. A plain scale can only be read directly to one subdivision. The diagonal construction therefore extends precision without changing the representative fraction.

Question 38Geometrical Construction and Scales

A diagonal scale is constructed with a representative fraction of 1:50 to read metres and decimetres. What is the least count that the diagonal subdivision allows?

  1. 1 millimetre
  2. 1 metre
  3. 1 decimetre
  4. 1 centimetre Correct answer.

Explanation

The diagonal construction splits each decimetre division into ten equal parts by similar triangles, so the smallest readable unit is one centimetre. The plain portion alone would only reach decimetres. Each further diagonal subdivision divides the previous unit by ten.

Question 39Geometrical Construction and Scales

A scale of chords is most directly used to do which of the following?

  1. Construct a parabola from a directrix
  2. Divide a line into equal parts
  3. Set out or measure angles without a protractor Correct answer.
  4. Measure the radius of an arc

Explanation

The scale of chords is built from the chord lengths of a circle and allows angles to be laid off or read using dividers alone. It is a standard aid in geometrical construction when a protractor is unavailable. It does not measure radii or divide straight lines.

Question 40Geometrical Construction and Scales

A vernier scale is added to a plain scale mainly in order to do what?

  1. Increase the maximum length the scale can measure
  2. Read a fraction of the smallest main division Correct answer.
  3. Convert the scale to full size
  4. Replace the representative fraction with an angle

Explanation

A vernier works by comparing the main scale divisions with slightly shorter or longer vernier divisions, so the difference reveals a fraction of the least main division. This gives a finer reading without lengthening the scale. The representative fraction remains unchanged.

Question 41Geometrical Construction and Scales

On a vernier scale the main scale divisions are 1 mm apart and 10 vernier divisions coincide with 9 main divisions. What is the least count?

  1. 1.0 mm
  2. 0.01 mm
  3. 0.1 mm Correct answer.
  4. 0.9 mm

Explanation

The least count equals one main division minus one vernier division. One vernier division is 9/10 mm, so the difference is 1 minus 0.9, giving 0.1 mm. This is the smallest interval the instrument can resolve.

Question 42Geometrical Construction and Scales

A scale has a representative fraction of 1:25 and must measure up to 6 metres. What length of drawing is required for the full scale?

  1. 240 mm Correct answer.
  2. 600 mm
  3. 150 mm
  4. 24 mm

Explanation

Six metres equals 6000 mm, and dividing by the scale factor of 25 gives 240 mm. The full scale must therefore be drawn 240 mm long to cover the complete range. Dividing rather than multiplying is correct because the drawing is reduced.

Question 43Geometrical Construction and Scales

In constructing a diagonal scale, why is the first main division alone subdivided into ten parts while the remaining divisions stay whole?

  1. Because the first division is always drawn longer than the others
  2. Because only the fractional part of a reading needs finer subdivision Correct answer.
  3. Because the diagonal lines cannot cross whole divisions
  4. Because the other divisions are not part of the scale

Explanation

A reading consists of whole main divisions plus a fraction, so only one division needs fine subdivision. Subdividing every division would waste space and clutter the construction. The diagonal lines are then drawn only across that subdivided division.

Question 44Geometrical Construction and Scales

A map is drawn to a representative fraction of 1:50000. A straight road measures 8 cm on the map. What is its actual length in kilometres?

  1. 40 km
  2. 4 km Correct answer.
  3. 0.4 km
  4. 400 km

Explanation

Eight centimetres multiplied by 50000 gives 400000 cm, which equals 4000 m or 4 km. The scale factor converts the map length directly into the real length in the same unit. Converting centimetres to kilometres requires dividing by 100000.

Question 45Geometrical Construction and Scales

Which statement correctly distinguishes a reducing scale from an enlarging scale?

  1. A reducing scale has a representative fraction above one; an enlarging scale has one below one
  2. A reducing scale has a representative fraction below one; an enlarging scale has one above one Correct answer.
  3. A reducing scale uses diagonals; an enlarging scale uses a vernier
  4. Both have a representative fraction equal to one but differ in the number of divisions

Explanation

The representative fraction is drawing length over actual length, so a value below one means the drawing is smaller and the scale reduces. A value above one means the drawing is larger and the scale enlarges. The construction method used is independent of this classification.

Question 46Geometrical Construction and Scales

A plain scale is to read kilometres and hectometres up to 5 km with a representative fraction of 1:20000. What is the length of the scale?

  1. 250 mm Correct answer.
  2. 500 mm
  3. 50 mm
  4. 100 mm

Explanation

Five kilometres equals 5000000 mm, and dividing by 20000 gives 250 mm. This is the total drawn length needed to cover the full 5 km range. The main divisions would then be spaced at 50 mm per kilometre.

Question 47Geometrical Construction and Scales

In the diagonal scale construction, the diagonal is drawn across a rectangle whose sides are one main division and one subdivision. Which geometric principle justifies the fine readings obtained?

  1. Pythagoras theorem
  2. Angle bisection
  3. Similar triangles Correct answer.
  4. Circle tangent properties

Explanation

The diagonal cuts the parallel subdivision lines in proportion, so the horizontal intercepts decrease uniformly and form similar triangles. This proportional division is what allows the scale to be read to a second decimal place. The construction relies on parallelism rather than on right-angle relationships.

Question 48Geometrical Construction and Scales

What is the standard first step when constructing any plain scale for a given representative fraction and range?

  1. Mark the vernier divisions along the top edge
  2. Bisect the scale line with a compass
  3. Draw the diagonal lines across the first division
  4. Calculate the total length of the scale from the representative fraction Correct answer.

Explanation

The total drawn length must be determined first by dividing the maximum real length by the scale factor. Only then can the line be laid out and divided into main divisions and subdivisions. Diagonal, vernier, or bisection work follows after the basic line is established.

Question 49Geometrical Construction and Scales

A scale of 1:2.5 is used to draw a component. What does a drawn length of 30 mm represent on the actual component?

  1. 75 mm Correct answer.
  2. 12 mm
  3. 7.5 mm
  4. 300 mm

Explanation

A representative fraction of 1:2.5 means each drawn unit represents 2.5 real units. Multiplying 30 mm by 2.5 gives 75 mm on the actual component. Since the fraction is below one, the drawing is a reduction and the real part is larger.

Question 50Geometrical Construction and Scales

Which scale type is best suited to measuring lengths to two places of decimals on a single compact drawing?

  1. Diagonal scale Correct answer.
  2. Plain scale
  3. Scale of chords
  4. Full-size scale

Explanation

The diagonal scale subdivides one main division twice, giving readings to a second decimal place within a compact layout. A plain scale reaches only one subdivision, and the scale of chords measures angles rather than lengths. Full-size scale describes the size ratio, not the precision of subdivision.