We analyze the equations governing the evolution of distributions of the work
and the heat exchanged with the environment by a manipulated stochastic system,
by means of a compact and general derivation. We obtain explicit solutions for
these equations for the case of a dragged Brownian particle in a harmonic
potential. We successfully compare the resulting predictions with the outcomes
of experiments, consisting in dragging a micron-sized colloidal particle
through water with a laser trap