Water rises to a height h in a capillary tube lowered vertically into water to a depth l as shown in the figure. The lower end of the tube is now closed, the tube is the taken out of the water and opend again. The length of the eater column remaining in the tube will be
.

Options

A. zero
B. ` l + h `
C. `2h `
D. `h `

Answer

B

Explanation

Due to surface tension water rises into the capillary tube upto height h. it will so if the water in capillary tube is contact with water in vessel . In the absence of contact of water in tube and water in vessel, the water in tube will form concave meniscus on both the faces in tube. Thus, the total length of water column in tube = ` ( l + h ) `