Definition

1. Noun:
   • A unit of force in the foot-pound-second (FPS) system: The "pdl" is a unit of force defined as the force required to accelerate a mass of one pound at a rate of one foot per second squared. It is equal to approximately 0.1382 newtons.

Usage

• The "pdl" is a technical term used primarily in physics and engineering contexts, especially when discussing the foot-pound-second (FPS) system of units. It is largely historical and has been superseded by the newton in the International System of Units (SI).

Examples

• Noun:
  • The textbook defined the pdl as the force needed to accelerate a one-pound mass by one foot per second squared.
  • In the FPS system, force can be measured in poundals (pdl).

Advanced Usage

• Historical Context: The term "pdl" is an abbreviation for "poundal." It is part of the absolute English engineering system, which is distinct from the gravitational system that uses the pound-force (lbf).
• Unit Conversion: A common calculation involves converting poundals to newtons: 1 pdl ≈ 0.138254954376 newtons (often rounded to 0.1382 N).

Variants and Related Words

• Poundal (n): The full term for "pdl." It is synonymous and used interchangeably.
  • The poundal is a coherent derived unit in the FPS system.

Synonyms

• Unit of force: This is a general synonym, as "pdl" is a specific type of force unit. More specific synonyms from other systems include:
  • Newton (N): The SI unit of force.
  • Dyne: The unit of force in the centimeter-gram-second (CGS) system.

Notes on Meaning

• The "pdl" has only one specific technical meaning as a unit of force. It is not used in everyday language and does not have different meanings, idioms, or phrasal verbs associated with it.

Noun

1. a unit of force equal to the force that imparts an acceleration of 1 foot/sec/sec to a mass of 1 pound; equal to 0.1382 newtons