Question

If the capillarity rise in two tubes containing same liquid and made of same material are $6.6\text{cm}$ and $2.2\text{cm}$, then the ratio of the radii of the tubes is

• A. $1:3$
• B. $3:1$
• C. $1:2$
• D. $1:6$

Answer 1

The correct option is A $1:3$

The height $h$ to which the liquid rises in the tube is given by:
$h=\frac{2T\cos \theta }{r\rho g}$ $\therefore h\propto \frac{1}{r}$
$\therefore \frac{h_1}{h_2}=\frac{r_2}{r_1}$ or $\frac{r_1}{r_2}=\frac{h_2}{h_1}=\frac{2.2}{6.6}=\frac{1}{3}$