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3 years ago

What is the potential energy of 4kg object sitting on a 3m ledge?

Chemistry

1 answer:

bagirrra123 [75]3 years ago

6 0

Potential energy (Pe) = m*g*h

m = 4 kg
g = 10 m/s²
h = 3 m

And now:

Pe = 4*10*3

Pe = 120 Joules ou J

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Air at 7S°F and14.6 though a cfm(cubic ft per minute) and the The flow rate is 48000 psia flows though a rectangular duct of Ix2

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Explanation:

The given data is as follows.

Air is at $75^{o}F$ and 14.6 psia.

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$r_{H} = \frac{\text{free flow area}}{\text{wet perimeter}}$

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= $4 \times \frac{1}{3} ft$

= $\frac{4}{3}$ ft

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Q = VA

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= 24000 ft/min

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$R_{e}$ = $\frac{D \times V \times \rho}{\mu}$

= $\frac{\frac{4}{3} \times 24000 \times 0.0744}{0.0443}$ (as $\rho = 0.0744 lb/ft^{3}$ and $\mu$ = 0.0443 lb/ft. hr)

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$\frac{\Delta P}{L} = \frac{4f \rho V^{2}}{2Dg_{c}}$

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miskamm [114]

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