Free AutoCAD ACU Exam Flashcards

LINE creates a string of independent straight segments; moving or erasing one segment does not affect the others. PLINE creates one connected object that can mix straight and arc segments, making it the better choice for an outline you want to edit or offset as a single shape.

A ray is a semi-infinite construction line that starts at a picked point and extends toward infinity in one direction. It is used as temporary reference geometry for alignment and is often drawn on its own layer so it can be isolated or erased later.

Turning on ISODRAFT switches the crosshair to a 2D isometric grid and lets you cycle between the Top, Right, and Left isoplanes by pressing F5 (or Ctrl+E). The active isoplane determines which pair of isometric axes new lines and isocircles align to.

JOIN merges objects that touch end to end into a single object, and the result depends on what you select: collinear lines become one line, arcs sharing a center and radius become one arc, and a connected chain of lines and arcs becomes one polyline. The Join option of PEDIT does the same job for an existing polyline.

A window selection box, dragged left to right, selects only objects that fall entirely inside it. A crossing selection box, dragged right to left, selects every object it encloses or merely touches, so crossing boxes typically grab more objects for the same box size.

Every new drawing starts with a single Layer 0 that cannot be deleted or renamed. Objects drawn on Layer 0 with ByLayer color and linetype take on the properties of whatever layer a block containing them is inserted onto, which is why Layer 0 is the standard layer for building portable block geometry.

Freezing a layer hides it and excludes it from regeneration and plotting, which speeds up large drawings; thawing reverses this. Locking a layer keeps it visible and plottable but blocks editing of its objects; unlocking restores editing. Turning a layer off hides it and keeps it from plotting, but its objects still regenerate with the drawing.

The BLOCK command turns selected objects into a named block definition anchored to a base point you specify. That base point becomes the handle used to position the block every time it is later inserted.

INSERT places a copy (a block reference) of an existing block definition at a chosen insertion point, where you can set its scale and rotation angle before placing it. The EXPLODE command breaks an inserted block reference back into its separate original objects.

DesignCenter (ADCENTER) lets you browse another open or saved drawing and drag blocks, layers, or other named objects directly into the current drawing. For a quick one-off copy between open drawings, Copy with Base Point (Ctrl+Shift+C) followed by Paste as Block (Ctrl+Shift+V) pastes the selection as a new block at a precise point.

Endpoint snaps to the closest end of a line, arc, or polyline segment, while Midpoint snaps to the point exactly halfway along that same segment. The AutoSnap marker tells you which one is active before you click: a square for Endpoint and a triangle for Midpoint.

Intersection snaps to the point where two objects actually cross. Extension snaps to a point along the imaginary path beyond an object's endpoint, letting you locate a point that lines up with an edge that does not physically reach that far.

Perpendicular snaps to the point on an object that forms a 90-degree angle with the line you are drawing. Tangent snaps to the point on an arc or circle where a line would touch it without crossing into the curve.

Quadrant snaps to the nearest of the four 0/90/180/270-degree points on a circle, arc, or ellipse. Center snaps to the middle point of that same circle, arc, or ellipse rather than to a point on its edge.

Nearest snaps to whichever point on an object is closest to the crosshairs, useful for landing precisely on an edge that has no other defined feature point. Parallel keeps a new line running at the same angle as a reference object once you hover the cursor over that object first.

Geometric Center snaps to the centroid of a closed polyline or closed spline, such as a hexagonal outline, even though that shape has no arc or circle for a Center snap to use. It is a separate osnap from Center, which finds the center of an arc, circle, or ellipse.

M2P locates the exact midpoint between two points you pick in sequence, even when no object's real midpoint sits there. It is reached from the Shift+right-click object snap shortcut menu rather than the standing running osnap settings.

Object snap tracking projects temporary alignment paths from osnap points you pause over, letting you locate a point that lines up with existing geometry. Polar tracking instead displays alignment paths at fixed angle increments, such as every 15 or 45 degrees, regardless of nearby objects.

Absolute coordinates (x,y) measure from the drawing origin (0,0). Relative coordinates (@x,y) measure from the last point entered. Polar coordinates (@distance<angle) measure a distance and angle from the last point, which is the fastest way to enter a known length at a known direction.

Dynamic input shows editable coordinate and dimension tooltips next to the crosshairs as you draw, letting you type values directly on screen. Direct distance entry works alongside it: you move the cursor to set a direction, then type a length and press Enter to place a point that distance away.

The Properties palette (Ctrl+1) stays open and lists every property of the selected object or objects. Quick Properties is a smaller pop-up near the cursor that shows only the most commonly changed properties, such as layer and color, for faster edits.

MATCHPROP, aliased MA, copies properties such as layer, color, linetype, and lineweight from one source object onto one or more destination objects you select afterward. A Settings option lets you choose exactly which properties get copied.

MOVE relocates the selected objects to a new position and leaves nothing behind at the original location. COPY duplicates the selected objects at the new position while leaving the originals in place, and can place multiple copies in a single command.

ROTATE turns selected objects around a base point by an angle you specify, changing their orientation but not their shape. MIRROR reflects selected objects across a mirror line you define; by default it keeps the source objects, and answering Yes to the Erase source objects prompt leaves only the flipped copy.

SCALE resizes an entire selected object uniformly around a base point using a scale factor. STRETCH moves only the vertices or endpoints that fall inside a crossing selection, which lengthens or shortens objects without resizing the whole object.

Clicking a grip on a selected object starts Stretch mode by default. Pressing Enter or the spacebar after grabbing a grip cycles through Move, Rotate, Scale, and Mirror modes without leaving grip editing or reselecting the object.

TRIM shortens an object back to a cutting edge, and EXTEND lengthens it out to a boundary edge. In AutoCAD 2021 and later both default to Quick mode, which treats every object as a possible edge; Standard mode has you select the edges first. LENGTHEN needs no edge at all: it changes length by a delta, percent, or total value.

A rectangular array repeats objects in a grid defined by rows, columns, and spacing. A polar array repeats objects around a center point you specify, spaced by item count and the angle to fill, such as 8 items evenly spaced around 360 degrees.

OFFSET creates a parallel copy of a selected object at a distance you specify, or through a point you pick, on either side of the original. It is the standard way to build a second, evenly spaced outline from an existing line, polyline, or arc.

FILLET joins two objects with a rounded arc of a set radius; setting the radius to 0 instead trims or extends the objects to meet at a sharp, square corner. CHAMFER joins two objects with a straight angled corner, defined by two distances or by a distance and an angle.

TEXT, also called DTEXT, creates single-line text where each line typed is its own separate object. MTEXT opens an in-place paragraph editor and creates one multiline text object that wraps within a boundary you define, which suits notes and specifications better.

A text style stores reusable settings such as font, width factor, and default height that many text objects share. A style height of 0 makes TEXT prompt for a height each time, while a nonzero height fixes it and skips the prompt. Justification, rotation, and mtext wrapping width are set on each individual text object.

An MLEADER object bundles the leader line, arrowhead, landing, and its text or block content into a single editable object, so moving or restyling the leader automatically moves its content with it. A manually drawn line paired with separate text has no such link between the two.

A multileader's content can be Mtext (a note), a Block (a symbol such as a tag or balloon), or None (just the leader line and arrowhead). The content type is set in the multileader style or chosen when the leader is created.

DIMLINEAR measures a horizontal or vertical distance between two points, regardless of the angle of the object being measured. DIMALIGNED measures the true straight-line distance between two points, with the dimension line drawn parallel to that line, which matters for angled objects.

DIMRADIUS dimensions a circle or arc's radius and prefixes the value with R. DIMDIAMETER dimensions the same circle's full diameter and prefixes the value with the diameter symbol, so the two commands label different measurements of the same curve.

DIMCONTINUE chains a new dimension from the second extension line of the previously drawn dimension, creating a running series of adjacent measurements. DIMBASELINE instead starts every new dimension from the same first extension line, stacking dimension lines to show cumulative distance from one common origin.

The overall scale setting in a dimension style, the DIMSCALE variable, multiplies the size of dimension text, arrowheads, and offsets so they plot at a legible size; it does not change the measured values. Its default is 1, and for model-space plotting it is set to the inverse of the plot scale, such as 4 for a 1/4 plot scale.

The Pick Points method fills an area by clicking inside a closed boundary and letting AutoCAD detect the enclosing edges automatically. The Select Objects method instead requires you to click the actual boundary objects yourself, which helps when automatic boundary detection would pick up the wrong area.

The Match Properties option on the Hatch Creation ribbon copies the pattern, angle, scale, and color of an existing hatch object onto a new hatch you are creating, so a matching pattern can be applied to a different area without re-entering every setting.

Model space, accessed from the Model tab, is where drawing geometry is created at real-world full scale. A Layout tab represents paper space, an arrangement of one or more viewports used to compose and scale that geometry for printing on a specific sheet size.

A new layout can be started from a drawing template's predefined layout, the Layout Wizard, or by right-clicking a layout tab and choosing New Layout. Each new layout begins with a single default viewport that can be resized or replaced.

A layout can hold more than one viewport, each showing model space geometry independently, created or added with the MVIEW command. Multiple viewports let a single sheet show, for example, an overall view alongside a detail view at a different scale.

Selecting a layout viewport and setting its Standard Scale value in the Properties palette controls how large the model space geometry appears relative to the paper, which is how geometry is made to plot to scale rather than to an arbitrary zoom level.

Setting a viewport's Display Locked property to Yes locks its view scale, so zooming or panning while the viewport is active moves the whole layout instead of changing the scale the model plots at. Set it back to No when the view needs to change.

A title block is typically inserted as a block, or comes built into a drawing template's layout, and is sized to the paper space sheet rather than to model space geometry. It carries sheet information such as project name, scale, and drawing number.

The Page Setup Manager, opened with PAGESETUP, stores a named collection of plot settings for a layout, including plot device, paper size, plot area, and scale. Saved page setups can be applied to other layouts so every sheet plots with consistent settings.

The PLOT command opens the plot dialog for the current layout or the Model tab and sends that single sheet to a plotter, printer, or PDF file, using the plot device, paper size, and scale you choose there or import from a saved page setup.

The PUBLISH command sends a list of selected layouts to output in one batch, rather than plotting each sheet one at a time, and can combine them into a single multi-sheet PDF or DWF file. It relies on each layout's own saved page setup for its settings.

Setting a layout's plot scale to an exact ratio, such as 1:1 or 1:2, plots geometry at a true, measurable size on paper. Choosing Fit to Paper instead scales the plot automatically to fill the sheet, which is convenient for quick check prints but does not produce a dimensionally accurate plot.