If a capillary tube of radius 1 mm is immersed in water , the mass of water rising in the capillary tube is M . If the radius tube is doubled , then the mass of water , that rises in the capillary tube will be

Options

A. `M/2`
B. 2 M
C. 3 M
D. M

Answer

B

Explanation

For capillary rise , `h_(1)r_(1) = h_(2)r_(2)`
` :. (h_(2))/(h_(1)) = (r_(1))/(r_(2)) =1/2`
and M ` = pir^(2)h_(1)rho and M' = pi (2r)^(2) xx h_(p) xx rho `
` :. (M')/M = ((2r)/r )^(2) xx (1/2) = 4 xx 1/2 = 2 `
` :. M' = 2M `