text: The overall value for this quantity can be calculated knowing two j and two m quantum numbers in aproduct involving many square roots and factorials.
full_question: The overall value for this quantity can be calculated knowing two j and two m quantum numbers in aproduct involving many square roots and factorials. The commutator of this quantity with the Hamiltonian iszero, but the commutator for two of its component operators equals i times h-bar times the operator of theother component. Spherical harmonics are eigenfunctions of this quantity. This quantity equals h-bar timesthe square root of the azimuthal quantum number, times that number plus one. Vector addition of two formsof this quantity occurs in L-S coupling. Areal velocity is constant because it is conserved. For 10 points, namethis quantity that classically equals moment of inertia times angular velocity, and is symbolized L. 
first_sentence: The overall value for this quantity can be calculated knowing two j and two m quantum numbers in aproduct involving many square roots and factorials.
raw_answer: angular momentum operator [or L until "L-S coupling" is read] 