

InterviewSolution
Saved Bookmarks
1. |
A light clindrical vessel is kept on a horizontal surface. The base are is A. A hole of cross-sectional area a is made just at its bottom side (where alt ltA) fig. Find minimum coeffiecent of friction necessary for sliding of the vessel due to the impact of the emerging liquid. |
Answer» Let h be the height of liquid in vessel above the hole. Velocity of efflux, `upsilon = sqrt(2 gh)` Impact force of the imerging liquid on the vessel and liquid contents is `F = upsilon (dm)/(dt) = upsilon(a rho upsilon) = a rho upsilon^(2) = a rho 2 gh` `= 2 a rho gh ` The force of friction, `f = mu R =mu A h rho g` For just sliding the vessel , `f =F` so, `mu A h rho g = 2 a rho g h or mu = (2a)/(A)`. |
|