All categories

3 years ago

Which of the following statements is true of a mature technology?

Engineering

1 answer:

hoa [83]3 years ago

8 0

Answer:

I think it is( More expensive than immature technologies) I took engineering class and this question is still quite tricky.

Explanation:

You might be interested in

The pump of a water distribution system is powered by a 6-kW electric motor whose efficiency is 95 percent. The water flow rate

Sonja [21]

Answer:

a) Mechanical efficiency ( $\varepsilon$ )=63.15% b) Temperature rise= 0.028ºC

Explanation:

For the item a) you have to define the mechanical power introduced (Wmec) to the system and the power transferred to the water (Pw).

The power input (electric motor) is equal to the motor power multiplied by the efficiency. Thus, $Wmec=0.95*6kW=5.7 kW$ .

Then, the power transferred (Pw) to the fluid is equal to the flow rate (Q) multiplied by the pressure jump $\Delta P$ . So $P_W = Q*\Delta P=0.018m^3/s * 200x10^3 Pa=3600W$ .

The efficiency is defined as the ratio between the output energy and the input energy. Then, the mechanical efficiency is $\varepsilon=3.6kW/5.7kW=0.6315=63.15\%$

For the b) item you have to consider that the inefficiency goes to the fluid as heat. So it is necessary to use the equation of the heat capacity but in a "flux" way. Calling <em>H</em> to the heat transfered to the fluid, the specif heat of the water and $\rho$ the density of the water:

$[tex]H=(5.7-3.6) kW=\rho*Q*c*\Delta T=1000kg/m^3*0.018m^3/s*4186J/(kg \ºC)*\Delta T$ [/tex]

Finally, the temperature rise is:

$\Delta T=2100/75348 \ºC=0.028 \ºC$

7 0

3 years ago

A liquid water turbine receives 2 kg / s water at 2000 kPa, 20Â°C with a velocity of 15 m / s . The exit is at 100 kPa, 20Â°C, a

sveta [45]

Peppa Pig sjsjssjssjsjsjsjsjssjjsss

3 0

3 years ago

If an object is near the surface of the earth the variation of its weight with distance from the center of the earth can ofteb b

zalisa [80]

Answer:

h=32.1 km

Explanation:

<em>solution:</em>

using newton law of gravitational attraction and newton second law:

$W=\frac{Gmm_{E} }{r^{2} } \\a=\frac{Gm_{E}}{r^{2}} \\W=ma\\$

$m_{E}= mass of earth$

r= distance between two masses

at sea level

a=g

$r=R_{E}$

$a=\frac{Gm_{E}}{r^{2}}$ .............................(1)

$Gm_{E} =gR_{E}^2$ .........................(2)

by substituting (2) and (1) $a=g\frac{R_{E}^2 }{r^{2} }$ acceleration due to gravity at a distance r from the centre of the earth in terms of g (sea level)

so the weight of the object at a distance r from the centre of the earth (W=ma)

W=mg(Re^2/r^2)..........(3)

h the height above the surface of the earth: r=Re+h

putting the value of r in eq (3)

W=mg(Re/Re+h)^2

W=0.99 mg

solving for height h:

h=Re(1/√0.99)-(1))

h=32.1 km

4 0

3 years ago

An important fluid property is the kinematic viscosity which determines the viscous, or frictional, forces acting in a flow. The

Aleksandr [31]

Answer:- 400 K - 26.665

600 K - 53.67

Explanation: y−y1=(y2−y1)/(x2−x1)×(x−x1)

Basic usage of the interpolation formula to get the values of the required answers kinematic viscosities at 400 and 600 K

5 0

4 years ago

Question #7

Gre4nikov [31]

Answer:

The option that identifies why the bicycle cannot yet be created as a model in the scenario is;

Suzanne forgot to include the exact units of measurement that should be used

Explanation:

The design sketch turned over to the team that will work on the prototype by Suzanne should present all aspects of the design that will enable others working on the design and that make use of the sketch to have a clear understanding of what is required of them

Given that Suzanne has included the numbers that explain the relationship between the sketch and the real world object, the scale that shows the ratios and proportions of the sketch and the actual bicycle has been provided, however, given that the the machinist still need more information, the units of the measurement indicated in the drawing was not included, therefore, the actual dimensions and size that gives the length of the parts of the sketch and of the prototype to be made cannot be determined.

4 0

3 years ago