I need help Brain power might be needed

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I need help Brain power might be needed

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i need to access my brain

Basically tell me what I'm doing and what i did and how i can make mine legible

don't do work for me unless your desperate for somthing to do any one who helps shall get a virtual pat ont he back
 

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why dont you go to your tutor and explain that you are struggling and can they explain step by step.
 
Cause he did that twice and i was not taking it in
its bugging me i know its somthing to do with that bottom line of equations lacking numbers or somthing

I will take it tommorrow when its the final final due date.
 
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its not hard to see why he wouldnt accept it... if it was my work i would have showed another line, maybe 2 lines, of working between the 2nd last and last lines.
its not that hard to do that, even if you dont understand where the rest of the working came from...
 
OK, I know nothing about how to calculate the displacement BUT when I did A levels, I would always start out by explaining my calculations.
You start by saying q = a1v1 = a2v2
This, on its own makes no sense to me at all.

I would have said 'formula for displacement ; q= a1v1 = a2v2

a1v1 = a2v2
therefore v2 = a1v1 / a2
If
a1 = ...
a2 = ...
v1 = ...
v2 = ... (insert any known numbers)

{Then show your calculations by substituting the known numbers, so if you know a1 = 6, a2 = 8 and v1 = 9 (for example)}

Then
v2 = 6 x 9 / 8
v2 = 6.75

OK, so this is very simplistic but I was always taught to show all workings as though the examiner didn't know anything about the subject.
We were always told that even if we had the wrong answer, we would still get something if the examiner could see how we'd got to the end & therefore where we'd made the mistake - in the real world, you'd go over your calculations or have a colleague go over them & by showing all stages, the point where the error occurred should be obvious.
 
oh good something useful to do with my time. i'm using windows calculator so i dont have pi, this may create slight inaccuracies.


speed of flow at pool (v2) = (a1*v1)/a2

v2 = (area at inlet * speed of flow at inlet) / area at pool

v2 = ([pi*1.5*1.5] * 2) / (pi*1*1)

v2 = (7.0686*2) / 3.14159

v2 = 4.5cm/sec


now, calculating the rate of flow (Q) is a simple matter of q = v*a

q = 4.5cm/sec (v) * 3.14159cm^2 (a) = 14.137155cm^3/sec

q = 14.14 cm^3/sec


ok thats the easy bits done, now you need to determine the pressure at the inlet to achieve that flow rate. this requires the use of that wonderful Bernoulli equation, which is;
P1 + pgh1 + (1/2)pv1^2 = P2 + pgh2 + (1/2)pv2^2

we know we need 3 x 10^5 Pa at the pool (given), and we know the length of the pipes, so we have all the figures we need.

now i always hated this equation and i havent used it for at least 9 years so lets see how far we can get, but first i'm going to get something to eat, brb.
 
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I worked it out about 2 hours ago in lesson i got another one to do now :( different assignment

also your numbers are correct in my memory cheers all

Want me to rearrange it for you anyways?

a bit of heat energy and all that
 
oh good something useful to do with my time. i'm using windows calculator so i dont have pi, this may create slight inaccuracies.


speed of flow at pool (v2) = (a1*v1)/a2

v2 = (area at inlet * speed of flow at inlet) / area at pool

v2 = ([pi*1.5*1.5] * 2) / (pi*1*1)

v2 = (7.0686*2) / 3.14159

v2 = 4.5cm/sec


now, calculating the rate of flow (Q) is a simple matter of q = v*a

q = 4.5cm/sec (v) * 3.14159cm^2 (a) = 14.137155cm^3/sec

q = 14.14 cm^3/sec


ok thats the easy bits done, now you need to determine the pressure at the inlet to achieve that flow rate. this requires the use of that wonderful Bernoulli equation, which is;
P1 + pgh1 + (1/2)pv1^2 = P2 + pgh2 + (1/2)pv2^2

we know we need 3 x 10^5 Pa at the pool (given), and we know the length of the pipes, so we have all the figures we need.

now i always hated this equation and i havent used it for at least 9 years so lets see how far we can get, but first i'm going to get something to eat, brb.

my god id like to use your brain for 5 minutes it does work it weird ways:chin:
 
P1 + pgh1 + (1/2)pv1^2 = P2 + pgh2 + (1/2)pv2^2

we want P1, so lets rearrange it-

P1 = P2 + pg(h2-h1) + (0.5*p)(v2^2 - v1^2)

who's ya daddy bitch!

so now we simply stick in the values to solve P1, and we already know enough values to solve it (remember its water and vertical pipes)

hang on a minute, i think i've given enough assistance for one day, i'm not here to do your homework! surely you can solve it now, if you cant then let me know and i'll help some more.

EDIT: aww you did it already :(
 
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