Surface Tension (Conceptual Question)

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
4 replies · 3K views
SpringPhysics
Messages
104
Reaction score
0

Homework Statement


(Sorry if this topic belongs to another forum.)

The definition of surface tension is the force exerted parallel to the surface of a liquid along a line of unit length, perpendicular to the line. So if, hypothetically, when you place a needle on the surface of water, the water does not depress, how is the needle's weight being supported at all? Would the surface tension be completely parallel to the surface of the water, but in no way perpendicular to the line?
 
Physics news on Phys.org
SpringPhysics said:

Homework Statement


(Sorry if this topic belongs to another forum.)

The definition of surface tension is the force exerted parallel to the surface of a liquid along a line of unit length, perpendicular to the line. So if, hypothetically, when you place a needle on the surface of water, the water does not depress, how is the needle's weight being supported at all? Would the surface tension be completely parallel to the surface of the water, but in no way perpendicular to the line?

The water does depress.
 
Dadface said:
The water does depress.

So the equation for surface tension takes into account that the water depresses?
 
SpringPhysics said:
So the equation for surface tension takes into account that the water depresses?

Yes,you may get more information if you google angle of contact.