Question

Water rises in a capillary tube to a height h, it will rise to a height more than h_____________.

• A. on the surface of sun
• B. in a lift moving down with an acceleration
• C. at the poles
• D. in a lift moving up with an acceleration

Answer 1

The correct option is B in a lift moving down with an acceleration

$h=\frac{2T\cos \theta }{r\rho a}$

where $h=$ rise in tube

$T=$ surface tension

$\theta =$angle of contact

$r=$ radius of tube

$\rho =$ density of water

$a=$ acceleration

To increase $h,a$ should be decreased.

So when the lift moves downward, relative acceleration will be $|a-g|$ hence a will decrease.

Hence the correct option is (B).