Joule | joules unit
Thejoule-second(Js,orJ⋅s)istheproductofanSIderivedunit,thejoule(J),andanSIbaseunit,thesecond(s).[1]Thejoule-secondisaunitofactionorofangularmomentum.Thejoule-secondalsoappearsinquantummechanicswithinthedefinitionofPlancksconstant.[2]Angularmomentumistheproductofanobject’smomentofinertia,inunitsofkg⋅m2anditsangularvelocityinunitsofrad⋅s−1.Thisproductofmomentofinertiaandangularvelocityyieldskg⋅m2⋅s−1orthejoule-second.Plancksconstantrepresentstheenergyofawave,inunitsofjoule,dividedbythefrequenc...
The joule-second (J s, or J⋅s) is the product of an SI derived unit, the joule (J), and an SI base unit, the second (s).[1] The joule-second is a unit of action or of angular momentum. The joule-second also appears in quantum mechanics within the definition of Plancks constant.[2] Angular momentum is the product of an object’s moment of inertia, in units of kg⋅m2 and its angular velocity in units of rad⋅s−1. This product of moment of inertia and angular velocity yields kg⋅m2⋅s−1 or the joule-second. Plancks constant represents the energy of a wave, in units of joule, divided by the frequency of that wave, in units of s−1. This quotient of energy and frequency also yields the joule-second (J⋅s).
Base units[edit]In SI base units the joule-second becomes kilogram-meter squared-per second or kg⋅m2⋅s−1. Dimensional Analysis of the joule-second yields M L2 T−1. Note the denominator of seconds (s) in the base units.
Confusion with joules per second[edit]The joule-seco...