Question

A capillary tube of length (i) l = 60 cm, (ii) l = 50 cm and radius r = 1/4mm is immersed vertically into water. Find the capillary rise in both cases. Angle of contact = $0^{\circ }$. Take coefficient of surface tension as 72 dyne/cm, g = 1000 cm $s^{-12}$.

• A. 57.6 cm
  
• B. 7.6 cm
• C. 6 cm
  
• D. 5 cm
  

Answer 1

The correct option is A 57.6 cm

57.6 cm
Sln :
$h=h_0=\frac{2Tcos\theta }{pgr}$
After substituting the value = 57.6 cm
a. Since l (= 60 cm) > $h_0$
b. Since l (= 50 cm) < $h_0$