Ask question

Ask question

All categories

3 years ago

12

A water pump delivers 3 hp of shaft power when operating. If the pressure differential between the outlet and the inlet of the p

ump is measured to be 1.2 psi when the flow rate is 8 ft^3/s and the changes in velocity and elevation are negligible, determine the mechanical efficiency of this pump.

1 answer:

Natali [406]3 years ago

5 0

Answer:

Mechanical Efficiency = 83.51%

Explanation:

Given Data:

Pressure difference = ΔP=1.2 Psi

Flow rate = $V=8ft^3/s\\$

Power of Pump = 3 hp

Required:

Mechanical Efficiency

Solution:

We will first bring the change the units of given data into SI units.

$P=1.2*6.895 = 8.274KPa\\V=8*0.00283=0.226 m^3/s\\P=3*0.746=2.238KW$

Now we will find the change in energy.

Since it is mentioned in the statement that change in elevation (potential energy) and change in velocity (Kinetic Energy) are negligible.

Thus change in energy is

$=(Mass * change in P)/density\\= \frac{M*P}{p}\\\\$

As we know that Mass = Volume x density

substituting the value

Energy = Volume * density x ΔP / density

Change in energy = Volumetric flow x ΔP

Change in energy = 0.226 x 8.274 = 1.869 KW

Now mechanical efficiency = change in energy / work done by shaft

Efficiency = 1.869 / 2.238

Efficiency = 0.8351 = 83.51%

You might be interested in

Technician A says that 18 gauge AWG wire can carry more current flow that 12 gauge AWG wire. Technician B says that metric wire

denpristay [2]

Answer:

Technician B

Explanation:

Both AWG and metric are sized by cross-sectional area.

Technician A is wrong: 12 gauge wire is larger diameter rated for 20 amps in free air. 18 awg is smaller diameter and typically used for speaker wiring, Class II or low voltage and sub-circuits within appliances.

6 0

3 years ago

Let suppose, you are going to develop a web-application for school management system. Then what architectural pattern will you u

Gnesinka [82]

Answer:

The architectural pattern i will use for the school management is the client-server pattern.

This pattern would consist of a server and many clients. wherein the server component would provide services to that of the clients and its components as specified and also there would be a client request service from that of the server.

Explanation:

Solution

A school management system would always involve the client server pattern as this pattern would have a server and many clients wherein the server component would give services to that of the clients and its components as specified and also there would be a client request service from that of the server. This server would share the appropriate services to such clients and also listen to the client's requests.

Such kind of pattern would mostly be used for for the online platforms or application like that of document.

5 0

3 years ago

A 10-mm steel drill rod was heat-treated and ground. The measured hardness was found to be 290 Brinell. Estimate the endurance s

grandymaker [24]

Answer:

the endurance strength $S_e$ = 421.24 MPa

Explanation:

From the given information; The objective is to estimate the endurance strength, Se, in MPa .

To do that; let's for see the expression that shows the relationship between the ultimate tensile strength and Brinell hardness number .

It is expressed as:

$200 \leq H_B \leq 450$

$S_{ut} = 3.41 H_B$

where;

$H_B$ = Brinell hardness number

$S_{ut}$ = Ultimate tensile strength

From ;

$S_{ut} = 3.41 H_B$ ; replace 290 for $H_B$ ; we have

$S_{ut} = 3.41 (290)$

$S_{ut} =$ 988.9 MPa

We can see that the derived value for the ultimate tensile strength when the Brinell harness number = 290 is less than 1400 MPa ( i.e it is 988.9 MPa)

So; we can say

$S_{ut} < 1400$

The Endurance limit can be represented by the formula:

$S_e ' = 0.5 S_{ut}$

$S_e ' = 0.5 (988.9)$

$S_e '$ = 494.45 MPa

Using Table 6.2 for parameter for Marin Surface modification factor. The value for a and b are derived; which are :

a = 1.58

b = -0.085

The value of the surface factor can be calculate by using the equation

$k_a = aS^b_{ut}$

$K_a = 1.58 (988.9)^{-0.085$

$K_a = 0.8792$

The formula that is used to determine the value of $k_b$ for the rotating shaft of size factor d = 10 mm is as follows:

$k_b = 1.24d^{-0.107}$

$k_b = 1.24(10)^{-0.107}$

$k_b = 0.969$

Finally; the the endurance strength, Se, in MPa if the rod is used in rotating bending is determined by using the expression;

$S_e =k_ak_b S' _e$

$S_e$ = 0.8792×0.969×494.45

$S_e$ = 421.24 MPa

Thus; the endurance strength $S_e$ = 421.24 MPa

8 0

3 years ago

PLEASE ANSWER FOR DRIVERS ED! WILL GIVE BRAINLIEST

Zepler [3.9K]

Answer:D

Explanation:

Google it it’s 100 ft

8 0

3 years ago

Assume the availability of an existing class, ICalculator, that models an integer arithmetic calculator and contains: an instanc

shtirl [24]

We connect with computers through coding, often known as computer programming.

<h3>How to code?</h3>

We connect with computers through coding, often understood as computer programming.
Coding exists similar to writing a set of instructions because it instructs a machine what to do.
You can instruct computers what to do or how to behave much more quickly by learning to write code.

class ICalculator {

int currentValue;

int add(int value) {

this.currentValue = currentValue + value;

return currentValue;

}

int sub(int value) {

this.currentValue = currentValue - value;

return currentValue;

}

int mul(int value) {

this.currentValue = currentValue * value;

return currentValue;

}

int div(int value) {

this.currentValue = currentValue / value;

return currentValue;

}

}

public class ICalculator2 extends ICalculator {

int negate() {

if (currentValue != 0)

this.currentValue = -currentValue;

return currentValue;

}

public static void main(String[] args) {

ICalculator2 ic = new ICalculator2();

ic.currentValue=5;

System.out.println(ic.add(2));

System.out.println(ic.sub(5));

System.out.println(ic.mul(3));

System.out.println(ic.div(3));

System.out.println(ic.negate());

}

}

To learn more about code, refer to

brainly.com/question/22654163

#SPJ4

3 0

1 year ago