A source of sound placed at the open end of a resonance column sends an acoustic wave of pressure amplitude ${\mathrm{\rho }}_0$ inside the tube. If the atmospheric pressure is ${\mathrm{\rho }}_{\mathrm{A}},$ then the ratio of maximum and minimum pressure at the closed end of the tube will be

• A

  $\frac{({\mathrm{\rho }}_{\mathrm{A}}+{\mathrm{\rho }}_0)}{({\mathrm{\rho }}_{\mathrm{A}}-{\mathrm{\rho }}_0)}$

• B

  $\frac{({\mathrm{\rho }}_{\mathrm{A}}+2{\mathrm{\rho }}_0)}{({\mathrm{\rho }}_{\mathrm{A}}-2{\mathrm{\rho }}_0)}$

• C

  $\frac{{\mathrm{\rho }}_{\mathrm{A}}}{{\mathrm{\rho }}_{\mathrm{A}}}$

• D

  $\frac{\left({\mathrm{\rho }}_{\mathrm{A}}+\frac{1}{2}{\mathrm{\rho }}_0\right)}{\left({\mathrm{\rho }}_{\mathrm{A}}-\frac{1}{2}{\mathrm{\rho }}_0\right)}$