Id say B.
Same principal as using gravity and a reduction in bore to make water cannon for gold mining. Was in a Clint film.. Pale Rider?
ER1C
Well-Known Member
Morning, Spot on my view as well, same as if you ever want to fire a garden hose harder to clear debris, squeeze your finger over it.
Hippo
Lord Hippo
They voted ferra sex o'fender.
There is no pressure at the exit of a pipe. Except for atmospheric pressure. All of the pressure energy is contained within the pipe. At the exit point, all of the energy becomes velocity energy. As discovered / explained by a very clever bloke called Bernoulli in the early 1700's.
Hippo
Lord Hippo
Yer but no but which one will squrt watta at yer pig wagon the hardest and wash the doors oft?
Need to know the pressure in the pipe and diameter of pipe. And any hydraulic head. Then the velocity at the pipe exit can be worked out. Muck cleaning ability is the impact of the jet when it hits something (in this case a tratter door), which is the mass x velocity of the water jet.
Morning All. 
Late again, been gassing on the blower.
Damp and dismal here. How much electric is Milliband's Eco-energy delivering today? Only 20% that's what 18% wind, 2% solar.
Absolute lunacy on a grand scale and we are all going to pay for it for decades to come.
Other than that minor rant, have a thoroughly thrilling Thursday!
Late again, been gassing on the blower.
Damp and dismal here. How much electric is Milliband's Eco-energy delivering today? Only 20% that's what 18% wind, 2% solar.
Absolute lunacy on a grand scale and we are all going to pay for it for decades to come.
Other than that minor rant, have a thoroughly thrilling Thursday!
Scottish island for sale. Eilean Loch Oscair. (you'll need to goggle it).
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Like it !
P= ma so the force, which you can measure as pressure, = the mass of the water x the speed it comes out at.
Oops, hang on, "a" is acceleration, so does that figure in it? Deceleration as it hits the thing that you use to measure the pressure?
Thing I need to redo my homework, but already it seems the question is a cheat one as pressure isn't the same as velocity.
I suppose you would have to see how much pressure you would have to exert to hold the water back by putting your hand or summat over the outlet.
And thinking like that I guess it would be much the same for all three.
Pardon me for not knowing all the equations and theory.
I vaguely remember Bernoulli. Have to look him up!
Exactly. Common misconception is that a water jet is pressure. It isn't. Its mass and velocity. Until it hits something. The question is flawed; Assuming the same pressure in all 3 of the larger sections of pipe, the pressure at the nozzle exit in all three cases is exactly the same - atmospheric pressure.
How about just inside the tip of the pipe then?
Now you've made me want to go "P"
With all the debate on this we need the output specs of the pump
.The pressure will be greatest at the pump or water inlet in situation B then A then C.
J
