text: The change in this quantity multiplies i in the exponential of the integral giving the atomic form factor.
full_question: The change in this quantity multiplies i in the exponential of the integral giving the atomic form factor.Einstein suggested that the change in this quantity for the far screen would determine which slit a photonpasses through. The "transfer" of this quantity, symbolized q, is a common term in scattering experiments.This quantity, divided by h-bar, gives the wavevector. The commutator of this quantity with x is i times h-bar.The energy of a photon equals the speed of light times this quantity. The Hamiltonian of a particle in a box isthe square of its operator, over twice the mass. The de Broglie wavelength is Planck's constant over thisquantity. For 10 points, name this quantity which, classically, equals mass times velocity. 
first_sentence: The change in this quantity multiplies i in the exponential of the integral giving the atomic form factor.
raw_answer: linear momentum