If \(M\) is the mass of water that rises in a capillary tube of radius \(r,\) then mass of water which will rise in a capillary tube of radius \(2r\) is:
1. \(M\)
2. \(4M\)
3. \(M/2\)
4. \(2M\)
 

A capillary tube made of glass of radius \(0.15 ~\text{mm}\) is dipped vertically in a beaker filled with methylene iodide (surface tension  \(=0.05 ~\text{Nm}^{-1},\) density \(=667~\text{kg m}^{-3}\)) which rises to height \(h\) in the tube. It is observed that the two tangents drawn from liquid-glass interfaces (from opp. sides of the capillary) make an angle of \(60^\circ\) with one another. Then \(h\) is close to:
(take \(g = 10~\text{m/s}^2\))
1. \(0.137~\text{m}\)
2. \(0.172~ \text{m}\)
3. \(0.087 ~\text{m}\)
4. \(0.049 ~\text{m}\)

When a long glass capillary tube of radius \(0.015~\text{cm}\) is dipped in a liquid, the liquid rises to a height of \(15~\text{cm}\) within it. If the contact angle between the liquid and glass to close to \(0^\circ\), the surface tension of the liquid, in milliNewton m^–1, is:\(\left[\rho_{\text {(liquid) }}=900 \mathrm{~kgm}^{-3}, \mathrm{~g}=10 \mathrm{~ms}^{-2}\right] \) (Give answer in closest integer).
1. \(200\)
2. \(101\)
3. \(402\)
4. \(325\)