Three liquids of densities `rho_1`,`rho_2` and `rho_3` (with `rho_1gtrho_2gtrho_2)` having the same value of surface tension `T`, rise to the same height in three identical capillaries. The angles of contact `theta_1`,`theta_2` and `theta_3` obeyA. `(pi)/(2)lttheta_1lttheta_2ltthetaltpi`B. `pigttheta_1gttheta_2gttheta_3gt(pi)/(2)`C. `(pi)/(2)gttheta_1gttheta_2gttheta_3ge0`D. `0letheta_1lttheta_2lttheta_3lt(pi)/(2)`

Three liquids of densities `rho_1`,`rho_2` and `rho_3` (with `rho_1gtr

1.	Three liquids of densities `rho_1`,`rho_2` and `rho_3` (with `rho_1gtrho_2gtrho_2)` having the same value of surface tension `T`, rise to the same height in three identical capillaries. The angles of contact `theta_1`,`theta_2` and `theta_3` obeyA. `(pi)/(2)lttheta_1lttheta_2ltthetaltpi`B. `pigttheta_1gttheta_2gttheta_3gt(pi)/(2)`C. `(pi)/(2)gttheta_1gttheta_2gttheta_3ge0`D. `0letheta_1lttheta_2lttheta_3lt(pi)/(2)`
Answer» Correct Answer - D `h=(2Tcostheta)/(rhogr)` as r,h, T are same `implies(costheta)/(rho)=`constant `implies=(costheta_1)/(rho_1)=(costheta_2)/(rho_2)=(costheta_3)/(rho_3)` as `rho_1gtrho_2gtrho_3` `impliescostheta_1gtcostheta_2gtcostheta_3` `impliestheta_1lttheta_2lttheta_3` As water rises `impliestheta` must be acutee So, `(0letheta_1lttheta_2lttheta_3ltpi)/(2)`

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