Acceleration

Pronunciation: /ækˌsɛləˈreɪ ʃən/ ?

When a car accelerates, it changes speed.[1] If a car is going 20 kilometers per hour (kph), and it accelerates to 30 kph it has changed speed by 10 kph. Acceleration is measured in units change in speed (velocity) per unit of time.

Graph of accelerate. At time=0, speed=50 meter per second. At time = 10s, speed = 60 meters per second.
Figure 1: Acceleration

If, at a point in time, an object is going 50 meters per second (mps) and 10 seconds later it is going 60 mps, the object's average acceleration is

(60 m/s - 50 m/s) / 10 s = 10 m/s / 10 s = 1 m/s^2.
1 m/s2 is read as, "One meter per second squared".

Sorry, the GeoGebra Applet could not be started. Please make sure that Java 1.4.2 (or later) is installed and active in your browser (Click here to install Java now)
Manipulative 1: Acceleration. Created with GeoGebra.

Take an object is going 70 kph and 10 seconds later it is going 100 kph. Since hours is not the same unit of measure as seconds, one must first change the 10 seconds to hours:

10 seconds*(1 minute/60 seconds)*(1 hour/60 minutes)=(10*1*1 hours)/(3600)=(1/360)hours.

So the acceleration is

(100mph - 70mph) / (1 / 360 ) hours = 30 mph * 360 1/hours = 1080 m/h^2.

Acceleration is measured using a unit of speed or velocity divided by a unit of time. Speed is measured in distance divided by time. Putting these together, speed can be measures in unit of distance divided by unit of time squared. Some of the commonly used measures of acceleration are:

AbbreviationUnit of measure
m/h2kilometers per hour squared
k/h2kilometers per hour squared
m/s2meters per second squared
Table 1: Units of Measure of Acceleration

References

  1. acceleration. http://wordnet.princeton.edu/. WordNet. Princeton University. (Accessed: 2011-01-08). http://wordnetweb.princeton.edu/perl/webwn?s=acceleration&sub=Search+WordNet&o2=&o0=1&o7=&o5=&o1=1&o6=&o4=&o3=&h=.

More Information

  • McAdams, David. Velocity. allmathwords.org. All Math Words Encyclopedia. Life is a Story Problem LLC. 2009-03-12. http://www.allmathwords.org/article.aspx?lang=en&id=Velocity.
  • McAdams, David. Length. allmathwords.org. All Math Words Encyclopedia. Life is a Story Problem LLC. 2009-03-12. http://www.allmathwords.org/article.aspx?lang=en&id=Length.

Cite this article as:


Acceleration. 2009-12-24. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/a/acceleration.html.

Translations

Image Credits

Revision History


2009-12-24: Added "References" (McAdams, David.)
2008-12-13: Simplified wording (McAdams, David.)
2008-10-05: Expanded 'More Information' (McAdams, David.)
2008-09-16: Corrected math error (McAdams, David.)
2008-06-07: Corrected spelling errors (McAdams, David.)
2008-04-16: Initial version (McAdams, David.)

All Math Words Encyclopedia is a service of Life is a Story Problem LLC.
Copyright © 2005-2011 Life is a Story Problem LLC. All rights reserved.
Creative Commons License This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License