\(m=\frac{1}{g}\left(\frac{P_{1} A \ell_{1}}{\ell_{1}}-\frac{P_{2} A \ell_{2}}{\ell_{2}}\right)\)
\(\mathrm{m}=\frac{1}{\mathrm{g}}\left(\frac{\mathrm{nRT}}{\ell_{1}}-\frac{\mathrm{nRT}}{\ell_{2}}\right)\)
\(m=\frac{n R T}{g}\left(\frac{1}{\ell_{1}}-\frac{1}{\ell_{2}}\right)\)