In Bernoulli's equation, shouldn't P2 (Pressure at the exiting end) be negative as it is opposite to the direction of velocity or flow of fluid?

In Bernoulli's equation, shouldn't P2 (Pressure at the exiting end) be negative as it is opposite to the direction of velocity or flow of fluid?

Solution

 Yes, it is negative. We just don’t see the negative sign.

According to bernoulli’s equation:

p/ρg + V^2/2g + z =constant

which can be written as:

p1/ρg + (V1)^2/2g + z1 = p2/ρg + (V2)^2/2g + z2

or,

(p1/ρg + (V1)^2/2g + z1) - (p2/ρg + (V2)^2/2g + z2) = 0

So, we can see that, p2 is actually negative. Its just the rearrangement of the above equation, that causes the minus sign to disappear.