1. The problem statement, all variables and given/known data i was told that For a given fluid the velocity of fluid in contact with with solid boundary is equal to the velocity of solid boundary in a book . In another book , I was told that the velocity of fluid at the solid boundary is 0 , which is correct ? can someone explain ? 2. Relevant equations 3. The attempt at a solution imo , the first one is wrong , the second statement is correct , am i right ? can someone expalin pls?