Pressure and Velocity

<...then why ther is no equation to solve it in direct without volume or Flow as considereing...>

Try the Bernoulli Equation.

Guest

Bernoulli is true and has applications where it can and must be used.

The problem is however that some people want to apply it to flow in pipes where pressure equal static + working pressure plus friction losses (or minus in gravitational lines).

View it this way :- If reducing the pipe did increase pressure it would be possible to have a horizontal line and reduce it to deliver water against any head without a pump.

Try holding a funnel (without movement) with the wide end in the water and measure the flow or pressure at the outlet.