1.

Three liquids of densities rho_(1),rho_(2)andrho_(3)(rho_(1)gtrho_(2)gtrho_(3)) having samevalue of surface tension T,rise to the same heitht in three identical capillaries . The following relation is remain true ?

Answer»

`(pi)/(2)lttheta_(1)lttheta_(2)lttheta_(3)ltpi`
`pigttheta_(1)gttheta_(2)gttheta_(3)gt(pi)/(2)`
`(pi)/(2)gttheta_(1)gttheta_(2)gttheta_(3)gt0`
`0letheta_(1)lttheta_(2)lttheta_(3)lt(pi)/(2)`

Solution :When a capillaryis placedvertically in aliquid the rise of liquid,
`h=(2Tcostheta)/(lrhog)`
here h,2,T, and G are constant
`therefore(COSTHETA)/(rho)=` constant
`therefore(costheta_(1))/(rho_1)=(costheta_(2))/(rho_(2))=(costheta_(3))/(rho_(3))`
but `rho_(1)gtrho_(2)gtrho_(3)`
`thereforecostheta_(1)gtcostheta_(2)gtcostheta_(3)`
`thereforetheta_(1)lttheta_(2)lttheta_(3)`[cos is decreasing function in first phase] Water rise in all three capillaries , so angle is ACUTE angle ,
`therefore0letheta_(1)lttheta_(2)lttheta_(3)lt(pi)/(2)`


Discussion

No Comment Found