Acceleration
The rate at which the velocity of an object changes over time.
Acceleration can involve increasing speed, decreasing speed (deceleration), or changing direction, as all these are changes in velocity. It is also a vector quantity.
Word relationships
- quickening: Quickening implies only an increase in speed; acceleration includes any change in velocity (speed or direction).
- speeding up: A colloquial term for increasing speed, which is one type of acceleration.
- deceleration: A decrease in speed or magnitude of velocity.
- constant velocity: A state where there is no acceleration.
Commonly confused with
- Velocity: Velocity is speed in a given direction; acceleration is the rate of change of that velocity.
Word family
- accelerate (verb): to increase speed or rate
- accelerator (noun): a device for increasing speed
Collocations
- constant acceleration
- gravitational acceleration
- linear acceleration
- angular acceleration
- rate of acceleration
Example sentences
- "When a car brakes suddenly, it experiences negative acceleration, or deceleration." In a physics lesson.
- "The rocket's powerful engines provided the necessary acceleration to escape Earth's gravity." Describing a rocket launch.
- "A sprinter's initial acceleration from the starting blocks is crucial for a fast race." In sports.
Memory hook
Think of the 'ACCELERator' pedal in a car, which changes your 'ACCELERation'. Change in velocity
When not to use
In everyday language, 'acceleration' often implies only speeding up. In physics, remember it also includes slowing down or changing direction. Avoid using it loosely when 'speeding up' or 'quickening' would be more precise for a non-technical audience.
Fun facts
- The acceleration due to gravity near the Earth's surface is approximately 9.8 m/s².
- A common unit for acceleration is meters per second squared (m/s²).
Explore more words
accelerate, decelerate, agility, Depreciation, Calculus, accretion
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