Question

What power of an engine is required to pump 2450 N of water per second from a well 50 m deep to the surface?
(a) 2.45*10^3 watts
(b) 2.45*10^4 watts
(c) 2.45*10^5 watts
(d) none of these

Answer 1

@Michele_Laino please can you solve it?

Answer 2

okay so work is Fd so the answer is 2450 N times 50 m

Answer 3

wait... per second

Answer 4

ignore my last answer

Answer 5

I think you're right because a watt is a N-m/s, so the units work out

Answer 6

we have to consider the manometric head H, which is about 50 m, so the requested power P is:
\[\Large P = F\left( {H + h} \right) = 2450\left( {50 + 50} \right) = ...?\]
being h the deepness of the well

Answer 7

sorry H is equal to the ratio between the pressure difference and the specific weight of the water
and
H+h is the manometric head or manometric prevalence

Answer 8

would you please tell me a little about manometric head,50 m deepness is okay to understand but what about additional 50m that you added

Answer 9

since the formula for computing the power, is:
\[\large P = \frac{{FH}}{t}\]
where H is the total prevalence, whose formula is:
\[H = h + \frac{{\Delta p}}{\gamma }\]
\Delta p is the difference between the pressures