Contact angle of liquid drop on solid surface.2

amk_dbz

Can anyone explain point 44 of the attached pdf document on surface tension.

(Here's the link in case attachment doesn't work:
http://www.sakshieducation.com/EAMCE...0_198-208_.pdf

How is the surface tension direction found out?
{i know it tangential but in which direction along the tangent?}
Also why is surface tension for Solid-Air Surface considered when balancing forces on liquid?
Any help will be appreciated
Thank you.

Attached Files

12Surface tension _198-208_.pdf (71.0 KB, 0 views)