Definition

1. Noun:
   • A unit of energy in the International System of Units (SI): A joule is the standard unit of work or energy. It is defined as the amount of work done when a force of one newton displaces an object by one meter in the direction of the force.
   • A unit of electrical energy: Specifically, one joule is equal to the work done when an electric current of one ampere passes through a resistance of one ohm for one second.

Examples of Usage

• Noun:
  • Lifting a small apple one meter against Earth's gravity requires about one joule of energy.
  • The battery stores approximately 10,000 joules of electrical energy.
  • In physics, work is measured in joules.

Advanced Usage

• Scientific Context: The joule is used across physics, chemistry, and engineering to quantify energy, work, and heat.
  • The heat capacity of water is about 4.18 joules per gram per degree Celsius.
• Derived Units: Many common units are defined in terms of joules.
  • The kilowatt-hour, a unit for electricity billing, is equal to 3.6 million joules.

Variants and Related Words

• Kilojoule (kJ): A unit equal to one thousand joules.
  • The nutritional information lists the energy content in kilojoules.
• Megajoule (MJ): A unit equal to one million joules.
  • The rocket fuel provided several hundred megajoules of energy.

Synonyms

• Newton-meter (N·m): A synonymous unit for torque, though its use for energy is equivalent to the joule in the context of work.
• Watt-second (W·s): A direct equivalent, as one watt of power expended for one second equals one joule.

Related Phrases and Idioms

(Note: As a scientific unit, 'joule' is not typically used in idiomatic expressions or phrasal verbs. Its usage is primarily technical.)

Noun

1. English physicist who established the mechanical theory of heat and discovered the first law of thermodynamics (1818-1889)
2. a unit of electrical energy equal to the work done when a current of one ampere passes through a resistance of one ohm for one second