Difference between revisions of "Work"

(Edited for accuracy and added a couple more helpful facts.)
Line 1: Line 1:
Intuitively, the amount of work you do (say, in lifting an object) depends on both the amount of force you exert and the distance over which you have to exert this force. In the case of a constant force <math>F</math> exerted over a distance <math>d</math>, the amount of work done is defined to be:
+
'''Work''' is a physical quantity defined as the [[force]] exerted on an object over a certain distance. In the case of a constant force <math>F</math> over a distance <math>d</math>, the amount of work done is found using the equation:
  
<cmath>W=F\cdot d</cmath>
+
<cmath>W=Fdcos\theta</cmath>
  
The [[SI]] unit of work is the [[Joule]].  
+
This also implies that if a force on an object is perpendicular to the direction in which the object is moving, there is no work done. The most common uses of this fact are in that gravity does not do work on an object on a flat surface and that a rope does not do work on an object experiencing [[centripetal motion]].
 +
 
 +
Additionally, the amount of work done on an object is equal to the change in [[kinetic energy]]. That is,
 +
 
 +
<cmath>W_{net}=\Delta KE</cmath>
 +
 
 +
The [[SI]] unit of work is the [[Joule]].
 
==See Also==
 
==See Also==
 
*[[Force]]
 
*[[Force]]

Revision as of 23:21, 22 April 2012

Work is a physical quantity defined as the force exerted on an object over a certain distance. In the case of a constant force $F$ over a distance $d$, the amount of work done is found using the equation:

\[W=Fdcos\theta\]

This also implies that if a force on an object is perpendicular to the direction in which the object is moving, there is no work done. The most common uses of this fact are in that gravity does not do work on an object on a flat surface and that a rope does not do work on an object experiencing centripetal motion.

Additionally, the amount of work done on an object is equal to the change in kinetic energy. That is,

\[W_{net}=\Delta KE\]

The SI unit of work is the Joule.

See Also

This article is a stub. Help us out by expanding it.

Invalid username
Login to AoPS