Bernoulli’s theorem and it's assumptions

Bernoulli’s theorem states that in a steady flow of ideal incompressible fluid, the sum of pressure head, velocity head and potential head is constant along a stream line provided no energy is added or taken out by external source. Bernoulli’s equation
is (p/density*g)+(U2/2g)+Z=constant .The first term is the flow energy per unit weight (or) pressure head .The second term is the kinetic energy per unit weight (or) kinetic head. The third term Z is the potential energy per unit weight (or) potential head. The sum of these terms is known as total head.

all the assumptions taken when deriving the Bernoulli’s equation:-
i. Fluid is ideal and incompressible. 
ii. flow is steady 
iii. Flow is along the stream line ie. One dimensional. 
iv. The velocity is uniform over the section and is equal to mean velocity. 
v. The only forces acting on the fluid are the gravity forces and pressure forces. 
few applications of Bernoulli’s equation.
*flow through venturimeter 
* flow through orifice meter 
*flow through orfices & mouth pieces 
*flow over notches & weirs