  Heavy quarks lose energy in the hot and dense partonic soup through collision
and radiation and ultimately fragments to heavy ($D$ or $B$) mesons. The energy
loss imprinted in the transverse momenta ($p_T$) distributions of those mesons,
leads to the celebrated phenomenon of $jet-quenching$. An alternate measure of
in-medium energy loss, recently discussed by PHENIX Collaboration, comes
through the effective shift in transverse momentum spectra of hadrons recorded
in nucleus-nucleus collisions when it was compared to the same in proton-proton
collisions. We have advocated a similar formalism and estimated the fractional
energy loss of heavy mesons for Pb+Pb collisions at the LHC and Au+Au
collisions at RHIC experiment. We have parameterised the invariant momentum
yield of heavy mesons by Hagedorn function. The fit parameters and the
experimental data of jet-quenching are utilised to estimate the fractional
energy loss ($\Delta m_T$) of heavy mesons at RHIC and LHC experiment. The
$\Delta m_T$ is found to scale with the transverse mass ($m_T$) of heavy mesons
through a power law at different energies and centralities of collisions. We
have also calculated the total energy loss suffered by a charm quark in
quark-gluon plasma produced in Pb+Pb collisions at the LHC energies. The
evolution of the plasma is described by (2+1) dimensional longitudinal
boost-invariant ideal hydrodynamics. It is found the total energy loss of charm
quarks scales with the transverse mass of charm quarks through a similar power
law which supports our analysis of fractional energy loss.
