## Question

The limbs of a manometer consist of uniform capillary tubes of radii . Find out the correct pressure difference if the level of the liquid (density 10^{3} kg/m^{3}, surface tension ) in narrower tube stands 0.2 m above that in the broader tube.

### Solution

1863

If *p*_{1} and *p*_{2} are the pressures in the broader and narrower tubes of radii *r*_{1}and *r*_{2} respectively, the pressure just below the meniscus in the respective tubes will be

So that,

Assuming the angle of contact to be zero, i.e., radius of meniscus equal to that of capillary,

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