Practice Test Geeks(GD&T) Geometric Dimensioning and Tolerancing Certification Practice Test
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Symbols and Rules Flashcards

7 cards from real GD&T practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Symbols and Rules flashcards as text

  1. A 'basic dimension' in GD&T is identified on a drawing by:

    Answer: Enclosing the value in a rectangular box

    Basic dimensions are shown enclosed in a rectangular box and represent the exact theoretically perfect value from which toleranced dimensions are measured.

  2. What is the function of the 'tangent plane' modifier (T in a circle) in a GD&T callout?

    Answer: The tolerance applies to a plane contacting the high points of the surface

    The tangent plane modifier means the tolerance controls the orientation of a tangent plane that contacts the high points of the surface, not the entire surface form.

  3. Which GD&T characteristic uses two coaxial cylinders as its tolerance zone?

    Answer: Cylindricity

    Cylindricity requires all points of a cylindrical surface to lie within two coaxial cylinders separated by the specified tolerance.

  4. The 'projected tolerance zone' symbol (P in a circle) is most commonly applied to:

    Answer: Threaded holes or press-fit pins to control mating part interference

    Projected tolerance zones extend the position tolerance above a hole to the height of the mating pin or fastener, preventing interference during assembly.

  5. In GD&T, the term 'virtual condition' for an external feature at MMC is calculated as:

    Answer: MMC size plus the applicable geometric tolerance

    For an external feature (shaft) at MMC, virtual condition equals the MMC size plus the geometric tolerance, representing the worst-case boundary.

  6. Which symbol instructs the inspector to measure a feature while it is rotating about a datum axis?

    Answer: Circular Runout or Total Runout

    Both circular runout and total runout require the part to be rotated 360° about the datum axis while a fixed indicator records deviations.

  7. On a feature control frame, a datum letter followed by a material condition modifier (e.g., 'B(M)') means:

    Answer: The datum shift allowance applies based on the actual mating size of datum feature B

    Applying MMC to a datum reference allows datum shift — additional tolerance based on how far the datum feature departs from its MMC size.