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3 years ago

Adding moisture is the ONLY way to obtain saturated air from unsaturated air. a)-True b) False

Engineering

1 answer:

Aleksandr [31]3 years ago

7 0

Answer:

The statement is false.

Explanation:

A unsaturated mass of air can become saturated in 3 ways:

1) Adding moisture to the initially unsaturated air till it becomes saturated.

2) Mixing of 2 different air masses initially unsaturated but the mixture becomes saturated.

3) Reducing the temperature of the surrounding so that the capacity to hold moisture of the air mass decreases until it becomes saturated.

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The link acts as part of the elevator control for a small airplane. If the attached aluminum tube has an inner diameter of 25 mm

aksik [14]

Answer:

Tmax=14.5MPa

Tmin=10.3MPa

Explanation:

T = 600 * 0.15 = 90N.m

$T_max =\frac{T_c}{j} = \frac{x}{y} = \frac{90 \times 0.0175}{\frac{\pi}{2} \times (0.0175^4-0.0125^4)}$

=14.5MPa

$T_{min} =\frac{T_c}{j} = \frac{x}{y} = \frac{90 \times 0.0125}{\frac{\pi}{2} \times (0.0175^4-0.0125^4)}$

=10.3MPa

7 0

3 years ago

The artifacts that expand what humans are able to do are called:.?

omeli [17]

Where you from?England has so many school subjects,but my country hasn’t got it.Do you like it

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3 years ago

The input shaft to a gearbox rotates at 2300 rpm and transmits a power of 42.6 kW. The output shaft power is 34.84 kW at a rotat

Marrrta [24]

Answer:

Torque at input shaft will be 176.8695 N-m

Explanation:

We have given input power $P_{IN}=42.6KW=42.6\times 10^3W$

Angular speed = 2300 rpm

For converting rpm to rad/sec we have multiply with $\frac{2\pi }{60}$

So $2300rpm=\frac{2300\times 2\pi }{60}=240.855rad/sec$

We have to find torque

We know that power is given by $P=\tau \omega$ , here $\tau$ is torque and $\omega$ is angular speed

So $42.6\times 10^3=\tau \times 240.855$

$\tau =176.8695N-m$

So torque at input shaft will be 176.8695 N-m

4 0

4 years ago

A wet cooling tower is to cool 60 kg/s of water from 40 to 33°C. Atmospheric air enters the tower at 1 atm with dry-and wet-bulb

AveGali [126]

Answer:

32.06m³/s

0.62kg/s

Explanation:

Using our psychometric chart, at T1 = 22°C and wet bulb = 16°C, we have

h1 = 45.6kj/kg

v1 = 0.85m³/kg

w1 = 0.00923

At T2 = 30°C, T3 = 40°C, T4 = 33°C

h2 = 96.1kj/kg

w2 = 0.02579

h3 = 168kj/kg

h4 = 138kj/kg

Using the mass for rate balances for water and air, we have

m'(a1) = m'(a2) = m'(a)

m'(3) - m'(4) = m'(a) [w2 - w1] = m'(m)

Now, we use the energy balance equation to solve for the needed mass, m'(a). Mass flow rate of water, m'3 = 60kg/s

0 = m'(a)h2 + m'4h4 - m'(a)h1 - m'3h3

0 = m'(a) [h2 - h1] + [-m'(a) {w2-w1} + m'3]h4 - m'3h3

m'(a) = [m'3(h3 - h4) ] / [ h2 - h1 - (w2 - w1)h4

m'(a) = [60(168-138)] / 96.1 - 45.6 - (0.02579 - 0.00923)168

m'(a) = 60*30 / 50.5 - 0.01656*168

m'(a) = 1800 / 47.72

m'(a) = 37.72kg/s

Volume flow rate = m'(a) * v1

Volume flow rate = 37.72 * 0.85

Volume flow rate = 32.06m³/s

Mass flow rate of make up water =

m'(m) = m'(a) [w2 - w1]

m'(m) = 37.72 [0.02579 - 0.00923]

m'(m) = 37.72 * 0.01656

m'(m) = 0.62kg/s

4 0

3 years ago

Gina is about to use a fire extinguisher on a small fire. What factor determines the type of extinguisher she should use

amm1812

There’s 5 different types of fire extinguishers that you can differentiate by their color codes.

Red - Water based

Creme - Foam based

Blue - Powder based

Black - CO2 or carbon dioxide based

Yellow - Wet chemical based

What would determine the type of fire extinguisher used would be the class of fire it is.

Class A - Combustible materials ( i.e. paper, wood) Extinguishers to use - Red, Creme, Blue, and Yellow. (Do not use Black)

Class B - Flammable liquids ( i.e. paint, petrol, alcohol) Extinguishers to use - Creme, Blue, and Black. (Do not use Red or Yellow)

Class C - Flammable gases ( i.e. butane, methane) Extinguishers to use - Blue (Do not use Red, Creme, Black or Yellow)

Class D - Flammable metals ( i.e. lithium, potassium) Extinguishers to use - Blue (Do not use Red, Creme, Black or Yellow)

Class F - Deep fat fryers ( i.e. chip pans) Extinguishers to use - Yellow (Do not use Red, Creme, Blue or Black)

Electrical - any sort of electrical equipment

( i.e. computers, generators) Extinguishers to use - Blue and Black (Do not use Red, Creme or Yellow)

8 0

3 years ago

Read 2 more answers