penetrometer

[pĕn′ĭ-trŏmĭ-tər]
  1. A device for measuring the penetrating power of electromagnetic radiation, especially x-rays.
  2. A device for measuring the denseness, compaction, or penetrability of a substance, such as soil, agricultural produce, or semisolid petroleum products. A penetrometer typically measures the resistance of the substance to penetration to a given depth by a weight-driven cone or needle of a given shape.
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