We present a numerical study of the energy spectra and fluxes in the inertial range of turbulent Rayleigh-Bénard convection for a wide range of Prandtl number. We consider both free-slip and no-slip conditions for our simulation. Our results support the Kolmogorov-Obukhov (KO) scaling for velocity field for zero-Prandtl number and low-Prandtl number (P ≪ 1) convection. For large Prandtl number (P > 1) convection, the Bolgiano-Obukhov scaling (BO) appears to agree with the numerical results better than the KO scaling. We provide phenomenological arguments for the zero-Prandtl and low-Prandtl number convection.