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3 years ago

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What is the ratio between the viscosities of air and water at 10°C? What is the ratio between their kinematic viscosities at thi

s temperature?

1 answer:

Eduardwww [97]3 years ago

4 0

Answer:

d

Explanation:

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Compute the number of kilo- grams of hydrogen that pass per hour through a 6-mm-thick sheet of palladium having an area of 0.25

nydimaria [60]

Answer:

The number of kilo- grams of hydrogen that pass per hour through this sheet of palladium is $4.1 * 10^{-3} \frac{kg}{h}$

Explanation:

Given

x1 = 0 mm

x2 = 6 mm = 6 * $10^{-3}$ m

c1 = 2 kg/ $m^{3}$

c2 = 0.4 kg/ $m^{3}$

T = 600 °C

Area = 0.25 $m^{2}$

D = 1.7 * $10^{8} m^{2}/s$

First equation

J = - D $\frac{c1 - c2}{x1 - x2}$

Second equation

J = $\frac{M}{A*t}$

To find the J (flux) use the First equation

J = - 1.7 * $10^{8} m^{2}/s$ * $\frac{2 kg/m^{3} - 0.4 kg/m^{3}}{0 - 6 * 10^{-3} } = 4.53 * 10^{-6} \frac{kg}{m^{2}s }$

To find M use the Second equation

$4.53 * 10^{-6} \frac{kg}{m^{2}s}$ = $\frac{M}{0.25 m^{2} * 3600s/h}$

M = $4.1 * 10^{-3} \frac{kg}{h}$

4 0

3 years ago

A steam pipe passes through a chemical plant, where wind passes in cross-flow over the outside of the pipe. The steam is saturat

valina [46]

Answer:

a) the rate of heat transfer from the pipe to the air is 23.866 watts

b) YES, the rate of heat transfer changes to 3518.61 watt

Explanation:

Given that:

steam is saturated at 17.90 bar.

the pipe is stainless steel and has an outside diameter of 6.75 cm

length = 34.7 m

Air flows over the pipe at 7.6 m/s

Bulk fluid temperature of 27°C

we know that

hD/k = 0.028 (Re)^0.8 (Pr)^0.33

Outside diameter of pipe = 6.75 cm

length of the pipe = 34.7 m

velocity of air = 7.6 m/s

Cp of air = 1.005 kJ/Kgk

viscosity of air = 1.81 × 10⁻⁵ kg/(m.sec)

thermal conductivity of air = 2.624 × 10⁻⁵ kw/m.k

so as

hD/k = 0.028 (Re)^0.8 (Pr)^0.33

hD/k = 0.028 (Dvp / u)^0.8 (Cpu / k)^0.33

(h × 0.0675 / 2.624 × 10⁻⁵) = (0.028 ([0.0675 × 7.6 × 1.225] / [1.81 ×10⁻⁵])^0.8) (((1.005 × 1.81 × 10⁻⁵) / (2.624 × 10⁻⁵))^0.33))

h = 0.0414 w/m².k

a)

Now to find the rate of heat transfer Q

Q = hAΔT

Q = 0.0414 × (2π × 0.03375 × 34.7) × (105.383 - 27)

Q = 23.866 watts

therefore the rate of heat transfer from the pipe to the air is 23.866 watts

b)

Now the flow direction changes to parallel flow, then

(h × 0.0675 / 2.624 × 10⁻⁵) = (0.028 ([34.7 × 7.6 × 1.225] / [1.81 ×10⁻⁵])^0.8) (((1.005 × 1.81 × 10⁻⁵) / (2.624 × 10⁻⁵))^0.33))

h = 6.1036 w/m².k

so from the steam table, saturated steam at 17.70 bar, temperature of steam will be 105.383°C

so to find the rate of heat transfer Q

Q = hAΔT

Q = 6.1036 × (2π × 0.03375 × 34.7) × (105.383 - 27)

Q = 3518.61 watt

Therefore the rate of heat transfer changes to 3518.61 watt

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In Josiah Johnson Hawes and Albert Sands Southworth, Early Operation under Ether, Massachusetts General Hospital the elevated vi

Ronch [10]

C and A I think cause I don’t really remember this I done before it his to be C and A

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3 years ago

Someone please please help me and explain!! I will give brainliest if right!!!

Mariulka [41]

R=10+15+30

55 is the answer to the question

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Vending machine controller (adapted from Katz, "Contemporary Logic Design") Design and implement a finite state machine that con

babunello [35]

Answer:

Check the explanation

Explanation:

A vending machine controller is that type of machine that comes with a single serial port on the same chip as the programmable processor. The controller comprises of a port arbitrator that selectively attaches or links one of a number of serially communicating devices to this single serial port.

Kindly check the attached image to get the step by step explanation to the above question.

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3 years ago