Question

The nature of $r-h$ graph ('$r$' is radius of capillary tube and '$h$' is capillary rise) is:

• A. Straight Line
• B. Parabola
• C. Ellipse
• D. Rectangular hyperbola

Answer 1

Answer: (D)

Rectangular hyperbola

The relation between height of capillary rise and the radius of the tube is

$h=\frac{2T\cos \theta }{\rho gr}\propto \frac{1}{r}$

where $T$ is the surface tension.

Hence the nature of the curve is rectangular hyperbola.

Option D is correct.