noun
kinetic energy
ki-NET-ik EN-uhr-jee
Kinetic energy (noun) means the energy an object has because it is moving, equal to half its mass multiplied by the square of its speed, and measured in joules. Example: “A car travelling at twice the speed has four times the kinetic energy.”
noun
1
The energy an object has because it is moving, equal to half its mass multiplied by the square of its speed, and measured in joules.
"A car travelling at twice the speed has four times the kinetic energy."
"Braking converts kinetic energy into heat in the discs."
How to use kinetic energy
Learner’s notesIn plain EnglishThe energy something has because it is moving.
When to use it
Technical, standard in physics and engineering; also used loosely for 'momentum' in business writing.
Memory tip
Kinetic energy is a scalar, so it has no direction, unlike momentum which does.
Trace the full origin ↓
Easily confused with
Common pairings
kinetic energy of a moving body
convert kinetic energy
kinetic energy recovery
total kinetic energy
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A car travelling at twice the speed has four times the _____.
Etymology
From Greek kinetikos 'of motion', from kinein 'to move', plus energeia 'activity'.
Antonyms
Related words
Rhymes for kinetic energy
See all rhymes for kinetic energy →Frequently asked questions
What is the difference between kinetic and potential energy?
Kinetic energy is energy of motion, so an object only has it while it is moving. Potential energy is stored energy an object has because of its position or condition, such as a book on a high shelf or a stretched spring. A falling object converts potential energy into kinetic energy as it drops.
What is the formula for kinetic energy?
KE equals one half times mass times velocity squared, written KE = ½mv². Mass is in kilograms and velocity in metres per second, giving an answer in joules.
Why does doubling speed quadruple kinetic energy?
Because velocity is squared in the formula, so multiplying speed by two multiplies the energy by two squared, which is four. This is why stopping distances grow so sharply with speed.
What is the meaning of kinetic energy?
"kinetic energy" (noun) means the energy an object has because it is moving, equal to half its mass multiplied by the square of its speed, and measured in joules.
