The height data of the specimen is necessary to determine relative density at the desired number of gyrations.

• A. False
• B. Height data is not used for density
• C. Height data is necessary to determine relative density at the desired number of gyrations
• D. Height data is used only for calibration

Answer: (C)

In this gyratory compaction context, density comes from mass divided by volume. The specimen’s volume is a cylinder with V = π(D/2)^2 × h, so the height after a given number of gyrations directly sets the volume (with the mold diameter fixed). To calculate density at that gyration level, you need that height data along with the mass. Without height, you can’t determine volume, and thus can’t compute density or relative density at the specified gyrations. The height is not used only for calibration; it governs the density calculation itself.