Question

A galss capillary length `l=11`cm and inside diameter `d=20mum` is submerged vertically into water. The upper end of the capillary is sealed. The outside pressure is considered to be `1xx10^(5)(N)/(m^(2))` . To what length has the capillary to be submerged to make the water levels inside and outside the capillary coincide?
A. 1.2 cm
B. 2.4 cm
C. 1.4 cm
D. 2.8 cm

Answer 1

Correct Answer - C
`4T(l-x)=P_(0)dx` or `4Tl=P_(0)dx+4Tx`
or `x=(4Tl)/(P_(0)d+4T)` or `x=(l)/(1+(P_(0)d)/(4T))`