Computer Aided Drafting Questions and Answers

Answer: A

Correct answer: 1-Q, 2-P, 3-R

Three facilities for three different jobs. A layer groups entities by category and controls their line type, colour and visibility together. A block is a named group inserted repeatedly from one definition. And a dimension style governs how dimensions are drawn, without touching what they measure.

Answer: B

The geometry comes first at full size, then the scale that will fit the sheet, then the annotation scaled to suit it, and finally the plot setting. Sizing text before the scale is known guarantees having to do it again.

Answer: C

Correct answer: 1 and 2 only are correct

Statements 1 and 2 are sound practice: geometry is drawn full size and scaled only at plotting, and an associative dimension follows what it measures. Statement 3 is the habit the whole discipline exists to prevent - a point that looks right on screen may be a fraction of a unit out, and the error surfaces later in hatching, areas and modelling.

Answer: D

Correct answer: to store the drawing at more than one scale

Layers control category, not scale: they group entities so that line types, colours and visibility can be set together, and so that some categories can be plotted while others are suppressed. Scale is a property of the plot, and geometry should be drawn full size whatever it is eventually plotted at.

Answer: A

Correct answer: it removes the need to understand projection conventions

CAD draws what it is told, so first and third angle projection, sectioning, hidden detail and the rest remain the draughtsman’s responsibility entirely. What it genuinely gives is revision without redrawing, exact reuse of standard details, and measurement taken directly from the geometry.

Answer: B

Correct answer: a gap between two entities at a corner

Hatching and area measurement both need a genuinely closed boundary, and an outline that merely looks closed at screen resolution may have a gap of a fraction of a unit at a corner. Zooming in on each corner, or using the drawing’s own boundary check, finds it - and snapping to endpoints in the first place prevents it.

Answer: C

Correct answer: overridden with typed text rather than left associative

An associative dimension recalculates when the geometry changes, so a figure that has not moved with the stretch cannot be associative. The likeliest cause is that someone typed the value over the measurement, which silently and permanently breaks the link - and nothing on the drawing shows that it has been broken.

Answer: D

Correct answer: both the assertion and the reason are true and the reason explains the assertion

Both are true and the reason gives the mechanism. Plotting at 1:50 divides every drawn length by fifty, and annotation is drawn in the same space as the geometry, so it is reduced with everything else. Text intended to finish 3 mm high must therefore be drawn 150 mm high, and the same factor applies to arrowheads and hatch spacing.

Answer: A

Correct answer: the assertion is false although the reason offered is a true statement in itself

It is true that a wireframe stores every edge exactly, but edges do not enclose anything: the model has no surfaces and therefore no inside, so no volume can be computed. It is also why a wireframe can be genuinely ambiguous about which face is nearer. Volume requires a surface or a solid model.

Answer: B

Correct answer: updates every drawing when the source file changes

This is exactly what an external reference is for. The grid lives in one file, every drawing points at it, and a change made once appears everywhere the next time those drawings are opened. A block would instead put a fixed copy inside each drawing, and each would have to be updated separately.