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Elena-2011 [213]

3 years ago

10

Technician A says it will save you money if you get a high interest rate from a bank on the loan. Technician B says it is always

better to lease a car than to own one. Who is correct

1 answer:

zubka84 [21]3 years ago

5 0

Is there a other option

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Define Electromechanical systems.

dedylja [7]

Answer:

Electromechanical systems or devices are systems or devices that involves the interaction between electrical systems and mechanical systems in which the motion of mechanical parts is converted to electrical energy or made to interact with energy or in which electrical energy is converted to mechanical energy or interacts with a moving mechanical system

Therefore;

Electromechanical systems convert <u>electrical energy</u> input into a <u>mechanical energy</u> output

Explanation:

3 0

3 years ago

What affect results when there is an impact between earth and is astroids check all that apply.

Vadim26 [7]

Answer:

Massive destruction

Explanation:

If the asteroid collides with the ground, a massive volume of dust will be blasted into the environment. If it collides with water, the amount of water vapour in the atmosphere will rise. This would result in more rain, which would cause earthquakes and mudslides.

As the asteroid collided with the Earth, massive volumes of dust were ejected into to the atmosphere. The sun's light were stopped from entering the Earth's surface, which is terrible news for plants.

6 0

3 years ago

Min is conducting an experiment where he compares the properties of water and lemonade. The first stage of the experiment is foc

madam [21]

Answer:

only if i knew

Explanation:

5 0

3 years ago

Write equations used to calculate the diode reverse saturation current, the voltage at which diode goes into resistive behavior,

laiz [17]

Answer:

Diode equation for reverse saturation current

$I_o = A\times e^{\frac{-Eg}{KT}} + B\times e^{\frac{-Eg}{2KT}}$

Voltage at which diode goes into Resistive region:V=-5 volts

Voltage at which high level injection occurs:Va=0.55 volt

Voltage at which avalanche multiplication occurs:V=5volts

Explanation:

we take here forward and reverse 0.7 volt and -5 volt

As Diode current equation is express as

$I_D = I_o \times (e^{\frac{V_D}{\eta V_T}} -1 )$ ....................1

here $I_D$ is total current through the diode and $I_o$ is reverse saturated current and $V_D$ is voltage drop across diode and $\eta$ is idealized factor and $V_T$ is thermal voltage

so here we know that when Bios is forward than

$V_D$ = $V_T$ .................2

ans Bios is Reverse than

$V_D$ = $V_R$ ..................3

so here

1. diode reverse saturation current is express as

$I_o = A\times e^{\frac{-Eg}{KT}} + B\times e^{\frac{-Eg}{2KT}}$

and

2. Voltage at which diode go into Reverse behavior will be

$V_D$ = $V_R$ = -5 volt

and

3. voltage at which high level injection occur that is

Va = 0.55 volt

and

4. voltage at which avalanche multiplication occurs is

Va = 5 volt

6 0

3 years ago

A pump is used to extract water from a reservoir and deliver it to another reservoir whose free surface elevation is 200 ft abov

babunello [35]

Answer:

a) the expected flow rate is 31.4 ft³/s

b) the required brake horsepower is 2808.4 bhp

c) the location of pump inlet to avoid cavitation is -8.4 ft

Explanation:

Given the data in the question;

free surface elevation = 200 ft

total length of pipe required = 1000 ft

diameter = 12 inch

Iron with relative roughness ( k/D ) = 0.0005

H $_{pump$ = 665-0.051Q² [Qinft ]

a) the expected flow rate

given that;

k/D = 0.0005

k/2R = 0.0005

R/k = 1000

now, we determine the friction factor;

1/√f = 2log₁₀( R/k ) + 1.74

we substitute

1/√f = 2log₁₀( 1000 ) + 1.74

1/√f = 6 + 1.74

1/√f = 7.74

√f = 1/7.74

√f = 0.1291989

f = (0.1291989)²

f = 0.01669

Now, Using Bernoulli theorem between two reservoirs;

(p/ρq)₁ + (v²/2g)₁ + z₁ + H $_p$ = (p/ρq)₂ + (v²/2g)₂ + z₂ + h $_L$

so

0 + 0 + 0 + 665-0.051Q² = 0 + 0 + 200 + flQ²/2gdA²

665-0.051Q² = 200 + flQ²/2gdA²

665-0.051Q² = 200 +[ ( 0.01669 × 1000 × Q² ) / (2 × 32.2 × (π/4)² × 1⁵ )

665 - 0.051Q² = 200 + [ 16.69Q² / 39.725 ]

665 - 200 - 0.051Q² = 0.420138Q²

665 - 200 = 0.420138Q² + 0.051Q²

465 = 0.471138Q²

Q² = 465 / 0.471138

Q² = 986.97196

Q = √986.97196

Q = 31.4 ft³/s

Therefore, the expected flow rate is 31.4 ft³/s

b) the brake horsepower required to drive the pump (assume an efficiency of 78%).

we know that;

P = ρgH $_p$ Q / η

where; H $_p$ = 665 - 0.051(986.97196) = 614.7

we substitute;

P = ( 62.42 × 614.7 × 31.4 ) / ( 0.78 × 550 )

P = 1204804.6236 / 429

P = 2808.4 bhp

Therefore, the required brake horsepower is 2808.4 bhp

c) the location of pump inlet to avoid cavitation (assume the required NPSH=25 ft).

NPSH = ( $P_{atom$ / ρg) - h $_s$ - ( P $_v$ / ρg )

we substitute

25 = ( 2116 / 62.42 ) - h $_s$ - ( 30 / 62.42 )

h $_s$ = 8.4 ft

Therefore, the location of pump inlet to avoid cavitation is -8.4 ft

6 0

3 years ago