phy 53 Lecture dr. brown 9 november 2010
fluid --
consider open glass of water...P_o 1 atm is approx 10^5 Pa
next seal the glass and get different pressure at top of water in the glass -- leads to --->
Pascal's principle
pressure applied to any part of an enclosed fluid is transmitted undiminished to all points in the fluid
applied to hydraulic system
archimedes
the bouyant force acting on an object (statically) immersed in a fluid is equal to the weight of the fluid displaced
showed archimedes lab idea...find unknown density
cork and lead in container filled with water -- lead suspended from top and cork held to bottom ...how are they displaced when the container is accelerated to right [lead to left and cork to right]
laminar fluid flow in a pipe
A_1 v_1 = A_2 v_2 [conservation of mass]
if fluid speeds up... pressure difference must cause
Bernoulli Formula -- work-mechanical energy theorem per unit volume
P + \frac{1}{2} \rho v^2 + \rho g h = constant
pressure = work per unit volume ;)