I'll buy a pint for the first TEF'er who can...

[The_Plagiarist]

I'm flying the flag for basic maths on this one:



Field = 3,000,000,000 m2 (3,000 km2)
Rainfall = 0.48m per m2 per year

0.48 x 3,000,000,000 = 1,444,000,000 m3 of rainfall
0.75 of that finds its way into the river = 1,080,000,000 cubic metres of water per year

River crosssection = 80m2 (20 x 4)

so 1,080,000,000 / 80 = 13,500,000 metres of water flows through that river crosssection per year

so the speed = 13,500,000 / 365days / 24hours / 60minutes / 60seconds = 0.428 metres per second


Degree level engineering it aint.

[BANGKOK RED]

Would it be a constant though.

Surely when the water in the field is deeper, the increased pressure would force it into the river quicker therefore increasing the flow.

[Nijholts Nuts]

A lot of it is hypothetical, obviously there is no field that is 3000k square and in real life there would be a lot of other contributing factors. I was revising fluid flow so thats all the question encompassed.

[BANGKOK RED]

In which case the correct answer would be: "how the fook do you expect me to answer the question without knowing all of the parameters".

It's a bit like asking "How long is a piece of string"

[Nijholts Nuts]

Degree level engineering it aint.

Im a University and it was a tutorial question given to me, you do the maths..

[Simon Pieman]

Would it be a constant though.

Surely when the water in the field is deeper, the increased pressure would force it into the river quicker therefore increasing the flow.

That's why it's average flow Einstein

[The_Plagiarist]

you're a university I'm a library, go figure...

[BrightonRed]

Living up to your name then Plagiarist? 

3,000km^2 = 3,000,000,000m^2
48cm = 0.48m
Volume of water that falls annually = 0.48 x 3,000,000,000 = 1,440,000,000m^3
Only 75% exits via the river = 0.75 x 1,440,000,000 = 1,080,000,000m^3 per year
1 year = 31,536,000 seconds
1,080,000,000 / 31,536,000 = 34.25m^3/sec
Average Velocity = Flow Rate / Cross Sectional Area
= 34.25m^3/sec / 80m^2
0.428m/s

I'm flying the flag for basic maths on this one:
Field = 3,000,000,000 m2 (3,000 km2)
Rainfall = 0.48m per m2 per year
0.48 x 3,000,000,000 = 1,444,000,000 m3 of rainfall
0.75 of that finds its way into the river = 1,080,000,000 cubic metres of water per year
River crosssection = 80m2 (20 x 4)
so 1,080,000,000 / 80 = 13,500,000 metres of water flows through that river crosssection per year
so the speed = 13,500,000 / 365days / 24hours / 60minutes / 60seconds = 0.428 metres per second
Degree level engineering it aint.