Question

Water rises to a height 3 cm in a capillary tube. If cross-sectional area of capillary tube is reduced to `(1/9)^"th"` of the initial area then water will rise to a height of ______.

Options

• 7 cm

• 9 cm

• 8 cm

• 6 cm

Answer 1

Water rises to a height 3 cm in a capillary tube. If cross-sectional area of capillary tube is reduced to `(1/9)^"th"` of the initial area then water will rise to a height of 9 cm.

Explanation:

h₁r₁ = h₂r₂

`h_1/h_2=r_2/r_1`

A ∝ r²

`sqrtA prop r`

`thereforeh_2=h_1sqrt(A_1/A_2)=3sqrt9=3xx3=9  "cm"`