Fill in the blanks:
$(i)$ Smaller the radius of the capillary tube,...... the height of the column. ( more / less )
$(ii)$ If the meniscus is convex,then the liquid .......... in the capillary,and if it is concave,then the liquid .......... in the capillary. ( depressed / rises up )

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(A) The height of the liquid column in a capillary tube is given by the formula $h = \frac{2T \cos \theta}{r \rho g}$,where $T$ is surface tension,$\theta$ is the angle of contact,$r$ is the radius of the tube,$\rho$ is the density of the liquid,and $g$ is the acceleration due to gravity.
$(i)$ Since $h \propto \frac{1}{r}$,as the radius $r$ of the capillary tube decreases,the height $h$ of the column increases. Therefore,the answer is 'more'.
$(ii)$ For a convex meniscus,the angle of contact $\theta > 90^\circ$,making $\cos \theta$ negative,which results in a depression of the liquid level. For a concave meniscus,the angle of contact $\theta < 90^\circ$,making $\cos \theta$ positive,which results in the liquid rising up. Therefore,the answers are 'depressed' and 'rises up' respectively.

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