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LC DCG practice questions

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Question 1Core: Graphical Communication and Technical Drawing

In a technical drawing, which line type is used to indicate a centre line of a circle or axis of symmetry?

  1. A chain line of long and short dashes Correct answer.
  2. A continuous thin line
  3. A continuous thick line
  4. A dashed hidden line

Explanation

Centre lines and axes of symmetry are drawn as chain lines, made up of alternating long dashes and short dashes, so they read clearly as reference lines rather than as object edges. Continuous thick lines show visible outlines, and dashed lines show hidden detail, so neither can mark an axis.

Question 2Core: Graphical Communication and Technical Drawing

A drawing is produced at a scale of 1:5. A feature measures 24 mm on the drawing. What is its true length?

  1. 19 mm
  2. 120 mm Correct answer.
  3. 29 mm
  4. 4.8 mm

Explanation

A scale of 1:5 means one unit on the drawing represents five units on the real object, so drawing measurements are multiplied by the denominator. Multiplying 24 mm by 5 gives a true length of 120 mm.

Question 3Core: Graphical Communication and Technical Drawing

Which projection method places the object between the observer and the plane of projection?

  1. Oblique projection
  2. Third-angle projection
  3. First-angle projection Correct answer.
  4. Isometric projection

Explanation

In first-angle projection the object sits between the observer and the projection plane, so the view is projected through the object onto the far plane. Third-angle projection places the plane between the observer and the object, which is why the symbol and view layout differ.

Question 4Core: Graphical Communication and Technical Drawing

In a standard orthographic layout, which view is normally placed directly below the front elevation?

  1. The isometric view
  2. The end elevation
  3. The auxiliary view
  4. The plan Correct answer.

Explanation

The plan is the view seen from above and, in both first- and third-angle layouts, is aligned vertically with the front elevation. End elevations are aligned horizontally to the side of the front elevation instead.

Question 5Core: Graphical Communication and Technical Drawing

What does the abbreviation 'ASME Y14.5' most directly govern in engineering drawing practice?

  1. Dimensioning and tolerancing conventions Correct answer.
  2. Colour coding of electrical cables
  3. Line weights for architectural hatching
  4. Scale ranges for site plans

Explanation

ASME Y14.5 is the standard for dimensioning and tolerancing, defining symbols and rules for limits, fits and geometric tolerancing. The other options relate to electrical, architectural or drafting practice rather than this dimensioning standard.

Question 6Core: Graphical Communication and Technical Drawing

Which type of pictorial drawing uses three axes equally spaced at 120 degrees with all three drawn to the same scale?

  1. Perspective drawing
  2. Isometric drawing Correct answer.
  3. Cabinet drawing
  4. Cavalier drawing

Explanation

An isometric drawing sets the three principal axes at 120 degrees to each other and uses a single scale along all of them, giving equal foreshortening. Cabinet and cavalier drawings are oblique methods with one axis at right angles to the picture plane.

Question 7Core: Graphical Communication and Technical Drawing

On a technical drawing, what is the primary purpose of a title block?

  1. To record drawing identification, scale and revision information Correct answer.
  2. To show the hidden internal features of the part
  3. To give the cutting plane for a section view
  4. To list every dimension used on the drawing

Explanation

The title block carries the administrative data of a drawing, such as its title, number, scale, date, author and revision status. Hidden detail, section planes and dimensions are conveyed by line work and annotation in the drawing area.

Question 8Core: Graphical Communication and Technical Drawing

A dimension of 40 mm is required on a drawing. Which of these is the correct way to write it in a standard metric drawing?

  1. mm 40
  2. 40 mm
  3. 40 Correct answer.
  4. 40MM

Explanation

In standard metric drawing practice the unit is stated once in a general note, and individual dimensions are written as plain numerals without the unit symbol. Repeating the unit on every dimension is therefore incorrect.

Question 9Core: Graphical Communication and Technical Drawing

A line of 30 mm on a drawing represents a real length of 1.5 m. Which scale has been used?

  1. 1:50 Correct answer.
  2. 1:500
  3. 1:20
  4. 1:5

Explanation

Convert the real length to the same unit, giving 1500 mm, then divide by the drawing length: 1500 divided by 30 equals 50, so the scale is 1:50. The ratio compares drawing size to real size, so the drawing is fifty times smaller than the object.

Question 10Core: Graphical Communication and Technical Drawing

In first-angle projection, where does the left-hand end elevation appear relative to the front elevation?

  1. Directly above the front elevation
  2. On the right of the front elevation Correct answer.
  3. Directly below the front elevation
  4. On the left of the front elevation

Explanation

In first-angle projection the view from the left is projected onto the plane on the far side of the object, so it appears on the right of the front elevation. Third-angle projection reverses this and places the left view on the left.

Question 11Core: Graphical Communication and Technical Drawing

A vertical cylinder is shown in orthographic projection. How does its top view appear?

  1. An ellipse
  2. A rectangle
  3. A circle Correct answer.
  4. A triangle

Explanation

Looking down the axis of a vertical cylinder shows the circular cross-section as a true circle. The front and side elevations show the curved surface as rectangles, which is why the plan is the view that reveals the circular shape.

Question 12Core: Graphical Communication and Technical Drawing

Which geometric construction is used to locate the centre of a given circle using only a straightedge and compasses?

  1. Drawing a chord and erecting a perpendicular at one end
  2. Drawing one diameter and halving it by eye
  3. Drawing two non-parallel chords and bisecting each perpendicularly Correct answer.
  4. Drawing two tangents and joining their points of contact

Explanation

The perpendicular bisector of any chord of a circle passes through the centre, so bisecting two non-parallel chords gives two lines that intersect at the centre. One chord alone is insufficient because its bisector is a single line containing infinitely many points.

Question 13Core: Graphical Communication and Technical Drawing

Which statement correctly describes a third-angle projection symbol?

  1. It shows two concentric circles with no connecting lines
  2. It shows a truncated cone with the large circle nearer the observer
  3. It shows a truncated cone with the small circle nearer the observer Correct answer.
  4. It shows a square with a diagonal cross inside

Explanation

The third-angle symbol places the truncated cone so that the smaller diameter circle is drawn on the side of the observer, with the trapezium opening away from it. The first-angle symbol is the mirror image, with the large circle toward the observer.

Question 14Core: Graphical Communication and Technical Drawing

A drawing shows a hole dimensioned as 'Ø20 H7'. What does the H7 designation specify?

  1. The material of the hole
  2. The tolerance class of the hole Correct answer.
  3. The surface finish of the hole
  4. The depth of the hole

Explanation

The letter gives the fundamental deviation and the number gives the tolerance grade, together defining the limits of size for the hole. A capital H indicates a hole whose lower limit is the basic size, and 7 sets the width of the tolerance zone.

Question 15Core: Graphical Communication and Technical Drawing

What is the effect of drawing a section view with hatching lines at 45 degrees?

  1. It indicates a dimension reference surface
  2. It indicates a hidden internal cavity
  3. It indicates solid material cut by the cutting plane Correct answer.
  4. It indicates a centre line of symmetry

Explanation

Hatching, usually thin lines at 45 degrees, is applied to the areas where the cutting plane has sliced through solid material. Cavities and holes remain unhatched, which is what makes the internal form readable.

Question 16Core: Graphical Communication and Technical Drawing

In an isometric drawing, how are true lengths along the three principal axes represented?

  1. They are drawn to the same scale on all three axes Correct answer.
  2. They are doubled on the two receding axes
  3. They are drawn to different scales on each axis
  4. They are halved on the vertical axis only

Explanation

An isometric drawing sets out the three axes at equal angles and uses one uniform scale along each, so equal real lengths appear equal on all three axes. This is what distinguishes it from oblique methods, where the receding axis may be drawn at half scale.

Question 17Core: Graphical Communication and Technical Drawing

A feature on a drawing is dimensioned as 25 ±0.2 mm. What is the permitted range of sizes?

  1. 24.8 mm to 25.0 mm
  2. 25.0 mm to 25.2 mm
  3. 24.8 mm to 25.2 mm Correct answer.
  4. 24.98 mm to 25.02 mm

Explanation

A bilateral tolerance of plus or minus 0.2 mm is added to and subtracted from the basic size, giving a maximum of 25.2 mm and a minimum of 24.8 mm. The total tolerance zone is therefore 0.4 mm wide.

Question 18Core: Graphical Communication and Technical Drawing

Which statement best explains why a broken-out section is used instead of a full section?

  1. It shows the whole object as if cut by a single plane through its centre
  2. It replaces the need for any hidden detail elsewhere on the drawing
  3. It is used only for symmetrical parts viewed along their axis
  4. It reveals a local internal feature while leaving most of the view as an external elevation Correct answer.

Explanation

A broken-out section removes only a small area of the view, bounded by a freehand break line, to expose a local internal feature. The rest of the view stays as an external elevation, which keeps the overall shape clear.

Question 19Core: Graphical Communication and Technical Drawing

A drawing is to be plotted on A3 paper from a CAD model. Which setting determines how the model is fitted to the sheet?

  1. The object snap mode
  2. The snap spacing
  3. The plot scale Correct answer.
  4. The grid display

Explanation

The plot scale controls the ratio between model units and plotted paper units, so it determines whether the drawing fits the sheet at a stated scale. Snap, grid and object snap are drafting aids that affect cursor behaviour rather than output size.

Question 20Core: Graphical Communication and Technical Drawing

A cone is cut by a plane parallel to one of its generators. Which curve is produced at the intersection?

  1. An ellipse
  2. A circle
  3. A hyperbola
  4. A parabola Correct answer.

Explanation

A plane parallel to a generator of a cone cuts it in a parabola, which is one of the classical conic sections. A plane at a shallower angle than the generator gives an ellipse, and a plane parallel to the axis gives a hyperbola.

Question 21Core: Graphical Communication and Technical Drawing

A straight line is to be divided into seven equal parts using a straightedge and compasses. Which method is geometrically sound?

  1. Construct a perpendicular at each end and join the intersections
  2. Bisect the line repeatedly until seven segments are counted
  3. Draw an auxiliary line at an angle, step off seven equal divisions, then draw parallels to the line joining the last division to the line's end Correct answer.
  4. Divide the line's length by seven and measure each part with a rule

Explanation

The standard construction uses an auxiliary ray divided into seven equal steps, then parallels drawn through each step transfer those divisions onto the original line. This relies on similar triangles, so all seven parts are exactly equal without measurement.

Question 22Core: Graphical Communication and Technical Drawing

A shaft and hole are dimensioned as Ø30 h6 and Ø30 H7 respectively. What type of fit results?

  1. An interference fit
  2. A clearance fit Correct answer.
  3. A transition fit
  4. A force fit

Explanation

A lower-case h shaft has its upper limit at the basic size, so it is always at or below 30 mm, while a capital H hole is always at or above 30 mm. The hole is therefore never smaller than the shaft, which guarantees clearance.

Question 23Core: Graphical Communication and Technical Drawing

A point lies 30 mm in front of the vertical plane and 20 mm above the horizontal plane. In first-angle projection, where do its front view and top view appear relative to the reference line?

  1. Front view 20 mm above the line, top view 30 mm below the line Correct answer.
  2. Front view 30 mm above the line, top view 20 mm below the line
  3. Front view 30 mm below the line, top view 20 mm above the line
  4. Front view 20 mm below the line, top view 30 mm above the line

Explanation

In first-angle projection the front view is obtained by looking from the front and is placed above the reference line at a height equal to the point's height above the horizontal plane, so 20 mm. The top view is placed below the line at a distance equal to the point's distance in front of the vertical plane, so 30 mm.

Question 24Core: Graphical Communication and Technical Drawing

A drawing uses a scale of 1:200. A rectangular site measures 45 mm by 30 mm on the drawing. What is its true area?

  1. 0.54 m²
  2. 540 m²
  3. 13.5 m²
  4. 54 m² Correct answer.

Explanation

Multiply each drawing dimension by 200 to get 9000 mm by 6000 mm, which is 9 m by 6 m. The true area is therefore 54 square metres; note that areas scale by the square of the linear ratio.

Question 25Core: Graphical Communication and Technical Drawing

Which statement about the arrangement of dimensions on an orthographic drawing is correct?

  1. Dimensions should always be given from the drawing border
  2. Each feature should be dimensioned once, on the view where it appears most clearly Correct answer.
  3. Each feature should be dimensioned on every view where it is visible
  4. Dimensions should be placed inside the hatched area of a section

Explanation

Good practice is to dimension each feature once, on the view that shows its true shape or clearest outline, to avoid duplication and conflicting values. Repeating a dimension on several views creates ambiguity and is avoided in standard practice.

Question 26Core: Graphical Communication and Technical Drawing

In a technical drawing, which line type is used to represent a hidden edge or feature that is not visible in the current view?

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

Explanation

Hidden edges are shown using dashed lines (short dashes evenly spaced). Continuous thick lines represent visible outlines, while continuous thin lines are used for dimension lines, hatching, and leader lines. Chain lines indicate centre lines or cutting planes.

Question 27Core: Graphical Communication and Technical Drawing

When dimensioning a circle, which symbol is placed before the numerical value to indicate that it is a diameter?

  1. R
  2. Ø Correct answer.
  3. SR
  4. □

Explanation

The symbol Ø (a circle with a slash) precedes a dimension to indicate a diameter. The symbol R is used for radius, □ for a square feature, and SR for a spherical radius.

Question 28Core: Graphical Communication and Technical Drawing

In orthographic projection, which principle determines the arrangement of the three principal views?

  1. The views are arranged so that the largest view is always in the centre.
  2. The views are arranged according to the size of the object, with the smallest view on the left.
  3. The views are arranged according to the direction of viewing, with each view placed adjacent to the view from which it is projected. Correct answer.
  4. The views are arranged alphabetically: front, top, then side.

Explanation

In orthographic projection, views are positioned relative to each other based on the viewing direction. For example, in first-angle projection, the view from the left is placed on the right, and the top view is placed below the front view. The arrangement is not based on alphabetical order, size, or centring the largest view.

Question 29Core: Graphical Communication and Technical Drawing

What is the primary purpose of a centre line in a technical drawing?

  1. To show the dimension of a feature.
  2. To show the outline of a part.
  3. To indicate the centre of a circle or the axis of symmetry of a feature. Correct answer.
  4. To indicate a hidden edge.

Explanation

Centre lines (chain lines with long and short dashes) are used to indicate the centre of circles, axes of symmetry, and pitch circles. They are not used for visible outlines, hidden edges, or dimensioning.

Question 30Core: Graphical Communication and Technical Drawing

A rectangular block is shown in first-angle projection. The front view is 60 mm wide and 40 mm high. The top view is placed below the front view. What does the top view represent?

  1. The view from the right side of the object.
  2. The view from above the object. Correct answer.
  3. The view from below the object.
  4. The view from the left side of the object.

Explanation

In first-angle projection, the top view is obtained by looking at the object from above and is placed below the front view. The view from below would be placed above the front view. Left and right side views are placed on the opposite sides in first-angle projection.

Question 31Core: Graphical Communication and Technical Drawing

A drawing is to be produced at a scale of 1:50. A line on the drawing measures 36 mm. What is the actual length it represents?

  1. 180 mm
  2. 72 mm
  3. 720 mm
  4. 1800 mm Correct answer.

Explanation

A scale of 1:50 means that 1 unit on the drawing represents 50 units in reality. Therefore, 36 mm on the drawing represents 36 × 50 = 1800 mm actual length.

Question 32Core: Graphical Communication and Technical Drawing

A hole is dimensioned as Ø25 H7. What does the H7 specify?

  1. The material of the hole.
  2. The surface finish of the hole.
  3. The depth of the hole.
  4. The tolerance class for the hole, indicating the fundamental deviation and tolerance grade. Correct answer.

Explanation

The H7 designation is an ISO tolerance class for a hole. 'H' indicates the fundamental deviation (lower deviation is zero for H), and '7' indicates the standard tolerance grade (IT7). It does not specify material, surface finish, or depth.

Question 33Core: Graphical Communication and Technical Drawing

In a section view, what does the hatching pattern indicate?

  1. The area of the object that is hidden from view.
  2. The area of the object that has been cut by the cutting plane. Correct answer.
  3. The area of the object that is to be machined.
  4. The area of the object that is visible behind the cutting plane.

Explanation

Hatching lines are drawn at an angle (often 45°) to indicate the solid material that has been cut by the cutting plane. The visible edges behind the cutting plane are shown as continuous lines, not hatched. Hidden edges are generally omitted in section views, and hatching does not indicate machining.

Question 34Core: Graphical Communication and Technical Drawing

Which type of pictorial drawing shows one face of the object in true shape and the other faces receding to a single vanishing point?

  1. Oblique drawing
  2. Isometric drawing
  3. Orthographic drawing
  4. Perspective drawing Correct answer.

Explanation

Perspective drawing uses vanishing points to create a realistic view, with one face often parallel to the picture plane (one-point perspective). Isometric drawings have three axes equally inclined, oblique drawings have one face parallel to the picture plane but receding lines at an angle, and orthographic drawings are not pictorial.

Question 35Core: Graphical Communication and Technical Drawing

When constructing a regular hexagon given the distance across flats, which method is used to determine the side length?

  1. The side length is equal to the distance across flats divided by √3. Correct answer.
  2. The side length is equal to the distance across corners.
  3. The side length is equal to the distance across flats.
  4. The side length is equal to half the distance across flats.

Explanation

For a regular hexagon, the distance across flats (AF) is equal to √3 times the side length (s). Therefore, s = AF / √3. The distance across corners is twice the side length, and the side length is not equal to the distance across flats or half of it.

Question 36Core: Graphical Communication and Technical Drawing

A point P is located 30 mm above the horizontal plane and 20 mm in front of the vertical plane. In first-angle projection, where is the front view of P located relative to the XY line?

  1. 30 mm below the XY line
  2. 30 mm above the XY line Correct answer.
  3. 20 mm below the XY line
  4. 20 mm above the XY line

Explanation

In first-angle projection, the front view is projected onto the vertical plane. The distance of the point above the horizontal plane (30 mm) determines the height of the front view above the XY line. The distance in front of the vertical plane (20 mm) determines the distance of the top view below the XY line.

Question 37Core: Graphical Communication and Technical Drawing

A cone is cut by a plane that is inclined to the axis and makes an angle with the base that is greater than the semi-vertical angle of the cone. Which curve is produced?

  1. Hyperbola
  2. Circle
  3. Ellipse Correct answer.
  4. Parabola

Explanation

When a cone is cut by a plane inclined to the axis such that the angle with the base is greater than the semi-vertical angle, the section is an ellipse. A parabola occurs when the cutting plane is parallel to a generator, and a hyperbola when the plane is parallel to the axis or makes a smaller angle. A circle is produced when the plane is perpendicular to the axis.

Question 38Core: Graphical Communication and Technical Drawing

In a technical drawing, a dimension of 50 ±0.1 mm is given. What is the total tolerance?

  1. 0.2 mm Correct answer.
  2. 0.05 mm
  3. 0.4 mm
  4. 0.1 mm

Explanation

The total tolerance is the difference between the upper and lower limits. The upper limit is 50.1 mm and the lower limit is 49.9 mm, so the total tolerance is 0.2 mm. The value ±0.1 mm indicates the deviation from the nominal size, not the total tolerance.

Question 39Core: Graphical Communication and Technical Drawing

Which statement best explains why a revolved section is used in a technical drawing?

  1. To show the assembly relationship between two parts.
  2. To show the cross-sectional shape of a feature without requiring a separate section view. Correct answer.
  3. To show the hidden details of an internal feature.
  4. To indicate the machining allowance on a cast part.

Explanation

A revolved section is drawn directly on the view by rotating the cross-section 90° about an axis, allowing the shape of a feature (such as a rib or spoke) to be shown without an additional view. It does not primarily show hidden details, machining allowance, or assembly relationships.

Question 40Core: Graphical Communication and Technical Drawing

A shaft and hole are dimensioned as Ø40 h6 and Ø40 H7 respectively. What type of fit is produced?

  1. Transition fit
  2. Line fit
  3. Interference fit
  4. Clearance fit Correct answer.

Explanation

For a hole with H7 tolerance, the lower deviation is zero, so the minimum hole size is 40.000 mm. For a shaft with h6 tolerance, the upper deviation is zero, so the maximum shaft size is 40.000 mm. Since the maximum shaft is equal to the minimum hole, the fit is a clearance fit (minimum clearance zero). It is not an interference or transition fit.

Question 41Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

In orthographic projection, what is the relationship between the projectors and the principal planes of projection?

  1. The projectors are parallel to the planes of projection.
  2. The projectors are inclined at 45° to the planes of projection.
  3. The projectors are perpendicular to the planes of projection. Correct answer.
  4. The projectors converge at a single station point.

Explanation

Orthographic projection is a parallel projection in which the projectors are perpendicular to the plane of projection, so true shapes and lengths parallel to that plane are preserved. Oblique and perspective systems use inclined or converging projectors instead.

Question 42Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

A line is parallel to the horizontal plane and inclined to the vertical plane. Which view shows its true length directly?

  1. The plan Correct answer.
  2. The view on an auxiliary inclined plane
  3. The end view on an auxiliary vertical plane
  4. The front elevation

Explanation

A line parallel to a plane projects onto that plane at true length. Since the line is parallel to the horizontal plane, its plan is its true length, while the elevation is foreshortened.

Question 43Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

What does the first-angle symbol on a drawing sheet indicate?

  1. The drawing uses a reduced scale throughout.
  2. The plane of projection is placed between the observer and the object. Correct answer.
  3. The object is placed between the observer and the plane of projection.
  4. The drawing is a pictorial rather than orthographic view.

Explanation

In first-angle projection the object is imagined behind the plane of projection, so the plane lies between the observer and the object. This produces the characteristic truncated cone symbol with the small circle nearer the front view.

Question 44Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

In a standard three-view orthographic layout, which view is placed directly below the front elevation?

  1. The development
  2. The plan Correct answer.
  3. The end elevation
  4. The auxiliary view

Explanation

The plan is obtained by looking down on the object and is aligned vertically below the front elevation, sharing the same width. The end elevation is aligned horizontally beside the front elevation instead.

Question 45Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

A point lies 30 mm above the horizontal plane and 20 mm in front of the vertical plane. How is this written in descriptive geometry notation?

  1. a′ 30 above HP, 20 in front of VP Correct answer.
  2. a 20 above HP, 30 in front of VP
  3. a′ 20 above HP, 30 in front of VP
  4. a 30 above HP, 20 in front of VP

Explanation

The elevation is denoted with a prime (a′) and records the height above the horizontal plane, while the plan (a) records the distance in front of the vertical plane. Therefore a′ carries 30 above HP and the plan distance of 20 in front of VP.

Question 46Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

What is the trace of a plane?

  1. The shortest distance between two skew lines
  2. The outline of the object's silhouette in a pictorial view
  3. The line in which the plane meets a plane of projection Correct answer.
  4. The true shape of a section cut through a solid

Explanation

A plane extended until it meets a reference plane of projection produces an intersection line called a trace, such as the horizontal trace on the HP and the vertical trace on the VP. Traces are used to locate inclined planes in orthographic work.

Question 47Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

A solid rests on the horizontal plane and is cut by an auxiliary plane inclined to both HP and VP. What is the purpose of the auxiliary view in this construction?

  1. To show the true shape of the cut section Correct answer.
  2. To show the object at a reduced scale
  3. To indicate the direction of the light source
  4. To replace the front elevation permanently

Explanation

An auxiliary plane is chosen parallel to the cutting plane so that the section projects onto it at true shape. The auxiliary view therefore reveals the real outline and true angles of the cut face.

Question 48Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

When a line is inclined to both the horizontal and vertical planes, which construction sequence is used to find its true length?

  1. Draw the line's elevation only and measure it directly.
  2. Project the line onto the vertical plane twice, once from each end.
  3. Draw an auxiliary plane parallel to the line using the plan, then project to obtain true length and inclinations. Correct answer.
  4. Rotate the plan until the line is parallel to the XY line, then read the true length from the elevation.

Explanation

For a line inclined to both principal planes, a first auxiliary plane is set parallel to the line as seen in plan, giving true length and the inclination to HP. A second auxiliary view then yields the inclination to VP.

Question 49Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

A point is 25 mm above HP and lies on VP. How do its projections appear on the drawing?

  1. Both projections are 25 mm above XY.
  2. Both plan and elevation lie on the XY line.
  3. The plan lies on the XY line and the elevation is 25 mm above XY. Correct answer.
  4. The elevation lies on XY and the plan is 25 mm below XY.

Explanation

A point on the vertical plane has zero distance in front of VP, so its plan falls on the XY line. Its height above HP is unchanged, so the elevation sits 25 mm above XY.

Question 50Core: Descriptive Geometry (Orthographic and Auxiliary Projection)

A line 60 mm long is parallel to both HP and VP. What do its plan and elevation show?

  1. Both views show the line foreshortened below 60 mm.
  2. The plan shows 60 mm and the elevation shows a point.
  3. The elevation shows 60 mm and the plan shows a point.
  4. Both views show the line at 60 mm, parallel to XY. Correct answer.

Explanation

A line parallel to a plane projects onto that plane at true length, so both the plan and elevation show 60 mm. Because the line is parallel to both planes, both views run parallel to the XY line.