Definition

Noun: A weighing instrument consisting of a horizontal lever (the beam) that is supported at its center (the fulcrum). Two pans of equal weight are suspended, one from each end of the beam. An object of unknown mass is placed in one pan, and standard masses are added to the other pan until the beam returns to a horizontal, balanced position.

Usage

This term refers specifically to the classic, simple mechanical balance. It is a fundamental tool in science and commerce for measuring mass. - The chemist used a sensitive beam balance to measure the powder sample. - In the historical market, goods were weighed on a large beam balance.

Advanced Usage

• "to be in beam balance": This phrase can describe the state of the instrument when the beam is level and equilibrium is achieved.
  • Add weight until the scale is in beam balance.

Variants and Related Words

• Balance (n): A more general term for any instrument used for weighing.
• Scale (n): A common synonym, though often implying a more modern or complex device (e.g., digital scale).
• Fulcrum (n): The pivot point on which a lever, such as the beam of a balance, turns.
• Pan (n): The shallow container suspended from the beam to hold the items being weighed.

Synonyms

• Two-pan balance
• Equal-arm balance
• Laboratory balance (when referring to a precise scientific instrument of this type)

Related Phrases

• To strike a balance: This idiom, meaning to find a compromise, derives from the concept of achieving equilibrium on a balance scale, though it is not specific to the "beam balance."
• To hang in the balance: This idiom, meaning an outcome is uncertain, also derives from the imagery of a balance scale that has not yet settled.

Noun

1. a balance consisting of a lever with two equal arms and a pan suspended from each arm