  We analyze the potentials which arise from the D1--D5 brane (5D black hole).
In the sufficiently low energy ($\omega \ll 1$), we can derive the
Schrodinger-type equation with potential $V_N$ from the linearized equations.
In this case one can understand the difference between absorption cross section
for a free and two fixed scalars intuitively in terms of their potentials. In
the low temperature limit ($\omega \gg T_H$), one expects the logarithmic
correction to the cross section of a free scalar. However, we cannot obtain the
Schrodinger equation with potential for this case. Finally we comment on the
stability of 5D black hole.
