Definition

1. Noun:
   • An instrument for measuring variations in the gravitational field of the Earth: A scientific device used in geophysics to detect and measure small differences in the force of gravity at different locations on the Earth's surface. These variations can indicate underground features like mineral deposits, oil fields, or geological structures.
   • An instrument for determining the specific gravity of a liquid or solid: A laboratory device, also commonly called a hydrometer when for liquids, used to measure the density of a substance relative to the density of water.

Usage Examples

• Noun (Geophysical Instrument):
  • Geologists used a gravimeter to survey the area for potential oil reserves.
  • The subtle readings from the gravimeter suggested a dense mass of rock beneath the valley.
• Noun (Density Instrument):
  • The brewer used a gravimeter to check the specific gravity of the beer wort.
  • In the lab, we determined the purity of the sample using a gravimeter.

Advanced Usage

• Absolute gravimeter: A highly precise instrument that measures the absolute value of gravitational acceleration (g) at a point, often using laser interferometry to track a free-falling object in a vacuum.
  • The research station installed an absolute gravimeter to monitor long-term changes in gravity.
• Relative gravimeter: An instrument that measures the in gravitational force between two locations. It is more portable and commonly used for field surveys.
  • The field team carried a relative gravimeter from site to site to map the local gravity field.

Variants and Related Words

• Gravimetry (n): The scientific measurement and study of gravity or density.
  • Gravimetry is an essential technique in both geophysical exploration and analytical chemistry.
• Hydrometer (n): A specific type of gravimeter, typically a sealed glass tube with a calibrated scale, used for measuring the specific gravity (and thus density) of liquids.
  • A hydrometer is a simple form of gravimeter used for testing battery fluid or antifreeze.

Synonyms

• For measuring Earth's gravity: Gravity meter.
• For measuring specific gravity: Densimeter, hydrometer (for liquids).

Related Terms and Contexts

• Gravity survey: A geophysical exploration method that uses a network of gravimeter measurements.
  • The company conducted a gravity survey before drilling.
• Specific gravity: The ratio of the density of a substance to the density of a reference substance (usually water for liquids and solids).
  • The gravimeter provided a direct reading of the liquid's specific gravity.

Noun

1. a measuring instrument for measuring variations in the gravitational field of the earth
2. a measuring instrument for determining the specific gravity of a liquid or solid