Physics - Fluid Question with Solution | TestHub

Rise of a liquid in a capillary tube is given by, $\mathrm{h}=\frac{2\mathrm{T}\cos \theta }{\mathrm{r}\rho \mathrm{g}}$ or $\cos \theta =hr\rho g/2T$ where $\theta =$ angle of contact, $\mathrm{r}=$ radius of capillary tube $\mathrm{T}=$ surface tension $\rho =$ density of liquid now given that $h$, $T$ and $r$ are constants for all three liquids, and ${\rho }_1>{\rho }_2>{\rho }_3$, therefore $\cos {\theta }_1>\cos {\theta }_2>\cos {\theta }_3$ or ${\theta }_1<{\theta }_2<{\theta }_3$ now as the liquid is rising in all three capillaries therefore angles of contact will be acute, $0\le {\theta }_1<{\theta }_2<{\theta }_3<\frac{\pi }{2}$