Joule-second: Difference between revisions
Content deleted Content added
Wsmitchell3 (talk | contribs) Added definition in terms of base SI units |
|||
| Line 1: | Line 1: | ||
{{dablink|For information about the unit "joule/second" see [[watt]]}} |
{{dablink|For information about the unit "joule/second" see [[watt]]}} |
||
The '''joule-second''' is a unit equal to a [[joule]] multiplied by a [[second]], used to measure [[action (physics)|action]] or [[angular momentum]]. The joule-second is the unit used for [[Planck's constant]]. |
The '''joule-second''' is a unit equal to a [[joule]] multiplied by a [[second]], used to measure [[action (physics)|action]] or [[angular momentum]]. The joule-second is the unit used for [[Planck's constant]]. |
||
In [[SI]] base units, the joule-second is <math>\frac{kg \cdot m^{2}}{s}</math>. |
|||
==Action== |
==Action== |
||
Revision as of 05:56, 16 June 2009
The joule-second is a unit equal to a joule multiplied by a second, used to measure action or angular momentum. The joule-second is the unit used for Planck's constant.
In SI base units, the joule-second is .
Action
The action of a system has the dimensions of energy integrated over time; it is therefore measured in joule-seconds.
Angular momentum
The angular momentum of an object is the integral with respect to time of the torque on the object. Torque in the SI system has the unit N·m, so angular momentum has the unit N·m·s, or J·s.