  We study heavy light mesons in a QCD inspired quark model with the Cornell
potential$-\frac{4\alpha_{S}}{3r}+br+c$. Here we consider the linear term $br$
as the parent and $-\frac{4\alpha_{S}}{3r}+c$ i.e.the Coloumbic part as the
perturbation.The linear parent leads to Airy function as the unperturbed
wavefunction. We then use the Dalgarno method of perturbation theory to obtain
the total wavefunction corrected upto first order with Coulombic peice as the
perturbation.With these wavefunctions, we study the Isgur-Wise function and
calculate its slope and curvature.
