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3 years ago

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A cooking pan whose inner diameter is 20 cm is filled with water and covered with a 4-kg lid. If the local atmospheric pressure

is 101 kPa, determine the temperature at which the water starts boiling when it is heated

2 answers:

sashaice [31]3 years ago

8 0

Answer:

$T=100.2^0C$

Explanation:

The boiling point of the water depends only on the absolute pressure p. the atmospheric temperature is given by P=101000 pa and the pressure from the lid we calculate by dividing its weight with the surface area of lid. the weight is product of mass and the gravitational acceleration. surface area is calculated by given diameter.

$D=20cm=20cm.\frac{1m}{100cm} =0.2m\\A=D^2\pi /4\\p_{l} =W/A=\frac{m.g}{D^2\pi/4 }$

The absolute pressure p is sum of atmospheric pressure and the pressure from the weight of lid.

$p=p_{a} +p_{l} \\\\p=p_{a} +\frac{m.g}{D^2\pi /4} \\\\p=101000Pa+\frac{4kg.9.81m/s^2}{(0.2m^2)^2.\pi /4} \\p=102249Pa$

At this pressure the boiling temperature of water is 100.2.

Arisa [49]3 years ago

7 0

Explanation:

Below is an attachment containing the solution.

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The rolling process is governed by the frictional force between the rollers and the workpiece. The frictional force at the entra

adell [148]

Answer:

b)false

Explanation:

Rolling is a process in which work piece passes through rolls to produce desired out put of the work piece.Rolling is a metal forming process.

We know that friction force is responsible for motion of work piece between rolls.If friction force is so small at the entrance side then work piece will not enter in the forming zone and forming process will not occurs.So the friction force should be high at the entrance side and low at the exit side.

So given statement is wrong.

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2 years ago

A slab-milling operation is performed on a 0.7 m long, 30 mm-wide cast-iron block with a feed of 0.25 mm/tooth and depth of cut

denis23 [38]

Answer:

a) $T_m=1.787min$

b) $MRR=35259.7mm^3/min$

Explanation:

From the question we are told that:

Cast-iron block Dimension:

Length $l=0.7m=>700mm$

Width $w=30mm$

Feed $F=0.25mm/tooth$

Depth $dp=3mm$

Diameter $d=75mm$

Number of cutting teeth $n=8$

Rotation speed $N=200rpm$

Generally the equation for Approach is mathematically given by

$x=\sqrt{Dd-d^2}$

$X=\sqrt{75*3-3^2}$

$X=14.69mm$

Therefore

Effective length is given as

$L_e=Approach +object Length$

$L_e=700+14.69$

$L_e=714.69mm$

a)

Generally the equation for Machine Time is mathematically given by

$T_m=\frac{L_e}{F_m}$

Where

$F_m=F*n*N$

$F_m=0.25*8*200$

$F_m=400$

Therefore

$T_m=\frac{714.69}{400}$

$T_m=1.787min$

b)

Generally the equation for Material Removal Rate. is mathematically given by

$MRR=\frac{L*B*d}{t_m}$

$MRR=\frac{700*30*3}{1.787}$

$MRR=35259.7mm^3/min$

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2 years ago

If the old radiator is replaced with a new one that has longer tubes made of the same material and same thickness as those in th

Nookie1986 [14]

Answer: hello some parts of your question is missing attached below is the missing information

The radiator of a car is a type of heat exchanger. Hot fluid coming from the car engine, called the coolant, flows through aluminum radiator tubes of thickness d that release heat to the outside air by conduction. The average temperature gradient between the coolant and the outside air is about 130 K/mm . The term ΔT/d is called the temperature gradient which is the temperature difference ΔT between coolant inside and the air outside per unit thickness of tube

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Explanation:

we will use this relation

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3 years ago

What is an example of a class 2 lever?

9966 [12]

Answer:

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2 years ago

Read 2 more answers

Complete function PrintPopcornTime(), with int parameter bagOunces, and void return type. If bagOunces is less than 3, print "To

weqwewe [10]

Answer:

#include <iostream>

using namespace std;

void PrintPopcornTime(int bagOunces) {

if(bagOunces < 3){

cout << "Too small";

cout << endl;

}

else if(bagOunces > 10){

cout << "Too large";

cout << endl;

}

else{

cout << (6 * bagOunces) << " seconds" << endl;

}

}

int main() {

PrintPopcornTime(7);

return 0;

}

Explanation:

Using C++ to write the program. In line 1 we define the header "#include <iostream>" that defines the standard input/output stream objects. In line 2 "using namespace std" gives me the ability to use classes or functions, From lines 5 to 17 we define the function "PrintPopcornTime(), with int parameter bagOunces" Line 19 we can then call the function using 7 as the argument "PrintPopcornTime(7);" to get the expected output.

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