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3 years ago

6

A centrifugal pump provides a flow rate of 0.03 m/s when operating at 1750 rpm against 60 m head. Determine the pump's flow rate

and developed head if the pump speed is increased to 3500 rpm.

1 answer:

vitfil [10]3 years ago

5 0

Answer:240m

$Q=0.06m^3/s$

Explanation:

Given rpm increases from 1750 rpm to 3500 rpm

initial head 60 m and flow rate= $0.03 m^{3}/s$

Since unit speed remains same

therefore

$N_u=\frac{N}{\sqrt{H}}$

$\frac{1750}{\sqrt{60}}$ = $\frac{3500}{\sqrt{H}}$

H=240m

Also unit Flow remains same

$\frac{Q}{\sqrt{H}}$ = $\frac{Q}{\sqrt{H}}$

$\frac{0.03}{\sqrt{60}}$ = $\frac{Q}{\sqrt{240}}$

$Q=0.06m^3/s$

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Answer:

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The closed tank of a fire engine is partly filled with water, the air space above being under pressure. A 6 cm bore connected to

skelet666 [1.2K]

Answer:

The air pressure in the tank is 53.9 $kN/m^{2}$

Solution:

As per the question:

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$P_{tank} = 5.5\times 1\times 9.8 = 53.9\ kN/m^{2}$

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