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## Homework Statement

Hey, stuck on this question in my hydraulics course:

Question involves lubricating oil pumped around a large piece of machinery.

Density of oil = 810 km/m3.

Viscosity = 0.01 kg/m.s throughout the system.

Flow rate is 0.140 Litres/sec

Pipe diameter = 3mm

Pressure at point A = 1.55 kPa.

Point A is 5m above the ground.

Point B is 36.5m above the ground. Question requires pressure to be found at this point ignoring minor losses and friction.

## Homework Equations

Bernoulli

## The Attempt at a Solution

I attempted to solve this problem using Bernoulli equation: (p

_{A}/Pg)+(V

_{A}

^{2}/2g) + Z

_{A}= (p

_{B}/Pg)+(V

_{B}

^{2}/2g)+Z

_{B}, However the result I get is negative and looks all wrong.

We were given very limited information but I assume we have enough info to answer the question. I don't see how the pressure at point A could possibly be only 1.55 kPa, given the oil is being lifted 31.5m high and 1.55 kPa is many times less pressure than even a car tyre.

The flow rate also seems unrealistically high, and the pipe diameter seems unrealistically narrow.

The question only specifies "pressure = 1.55 kPa". Is it possible they meant dynamic pressure?