1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
maria [59]
3 years ago
10

A sphere is assumed to have the properties of water and has an initial heat generation 46480 W/m^3 How much should the heat gene

ration term be lowered, if the maximum temperature at the center of the spherical geometry is to be limited to 360 Kelvin? The radius of the sphere is 0.1m ambient air temperature is 25 C. Convert the resulting heat generation to Food Calories per hour
Engineering
1 answer:
Verdich [7]3 years ago
3 0

Answer:

Resulting heat generation, Q = 77.638 kcal/h

Given:

Initial heat generation of the sphere, Q_{Gi} = 46480 W/m^{3}

Maximum temperature, T_{m} = 360 K

Radius of the sphere, r = 0.1 m

Ambient air temperature, T = 25^{\circ}C = 298 K

Solution:

Now, maximum heat generation, Q_{m} is given by:

T_{m} = \frac{Q_{m}r^{2}}{6K} + T                     (1)

where

K = Thermal conductivity of water at T_{m} = 360 K = 0.67 W/m^{\circ}C

Now, using eqn (1):

360 = \frac{Q_{m}\times 0.1^{2}}{6\times 0.67} + 298

Q_{m} = 24924 W/m^{3}

max. heat generation at maintained max. temperature of 360 K is 24924W/m^{3}

For excess heat generation, Q:

Q = (Q_{Gi} - Q_{m})\times volume of sphere, V

where

V = \frac{4}{3}\pi r^{3}

Q = (46480 - 24924)\times \frac{4}{3}\pi\0.1^{3} = 21556\times \frac{4}{3}\pi\0.1^{3} W/m^{3}

Q = 90.294 W

Now, 1 kcal/h = 1.163 W

Therefore,

Q = \frac{90.294}{1.163} = 77.638 kcal/h

You might be interested in
Unit for trigonometric functions is always "radian". 1. 10 points: Do NOT submit your MATLAB code for this problem (a) Given f(x
RoseWind [281]

Answer:

Below is the required code.

Explanation:

%% Newton Raphson Method

clear all;

clc;

x0=input('Initial guess:\n');

x=x0;

f=exp(-x)-sin(x)-0.2;

g=-exp(-x)-cos(x);

ep=10;

i=0;

cc=input('Condition of convergence:\n');

while ep>=cc

i=i+1;

temp=x;

x=x-(f/g);

f=exp(-x)-sin(x)-0.2;

g=-exp(-x)-cos(x);

ep=abs(x-temp);

fprintf('x = %6f and error = %6f at iteration = %2f \n',x,ep,i);

end

fprintf('The solution x = %6f \n',x);

%% End of MATLAB Program

Command Window:

(a) First Root:

Initial guess:

1.5

Condition of convergence:

0.01

x = -1.815662 and error = 3.315662 at iteration = 1.000000

x = -0.644115 and error = 1.171547 at iteration = 2.000000

x = 0.208270 and error = 0.852385 at iteration = 3.000000

x = 0.434602 and error = 0.226332 at iteration = 4.000000

x = 0.451631 and error = 0.017029 at iteration = 5.000000

x = 0.451732 and error = 0.000101 at iteration = 6.000000

The solution x = 0.451732

>>

Second Root:

Initial guess:

3.5

Condition of convergence:

0.01

x = 3.300299 and error = 0.199701 at iteration = 1.000000

x = 3.305650 and error = 0.005351 at iteration = 2.000000

The solution x = 3.305650

>>

(b) Guess x=0.5:

Initial guess:

0.5

Condition of convergence:

0.01

x = 0.450883 and error = 0.049117 at iteration = 1.000000

x = 0.451732 and error = 0.000849 at iteration = 2.000000

The solution x = 0.451732

>>

Guess x=1.75:

Initial guess:

1.75

Condition of convergence:

0.01

x = 227.641471 and error = 225.891471 at iteration = 1.000000

x = 218.000998 and error = 9.640473 at iteration = 2.000000

x = 215.771507 and error = 2.229491 at iteration = 3.000000

x = 217.692636 and error = 1.921130 at iteration = 4.000000

x = 216.703197 and error = 0.989439 at iteration = 5.000000

x = 216.970438 and error = 0.267241 at iteration = 6.000000

x = 216.971251 and error = 0.000813 at iteration = 7.000000

The solution x = 216.971251

>>

Guess x=3.0:

Initial guess:

3

Condition of convergence:

0.01

x = 3.309861 and error = 0.309861 at iteration = 1.000000

x = 3.305651 and error = 0.004210 at iteration = 2.000000

The solution x = 3.305651

>>

Guess x=4.7:

Initial guess:

4.7

Condition of convergence:

0.01

x = -1.916100 and error = 1.051861 at iteration = 240.000000

x = -0.748896 and error = 1.167204 at iteration = 241.000000

x = 0.162730 and error = 0.911626 at iteration = 242.000000

x = 0.428332 and error = 0.265602 at iteration = 243.000000

x = 0.451545 and error = 0.023212 at iteration = 244.000000

x = 0.451732 and error = 0.000187 at iteration = 245.000000

The solution x = 0.451732

>>

Explanation:

The two solutions are x =0.451732 and 3.305651 within the range 0 < x< 5.

The initial guess x = 1.75 fails to determine the solution as it's not in the range. So the solution turns to unstable with initial guess x = 1.75.

7 0
3 years ago
What are the main microsoft ware packages widely used today​
RSB [31]

Answer:

» Microsoft word ( word processing )

» Microsoft powerpoint ( presentation )

» Microsoft access ( database mamagement )

» Microsoft excel ( spread sheets )

Explanation:

.

7 0
2 years ago
Read 2 more answers
Which of the following best describes the role of engineers
Fantom [35]

Problem Solvers

Explanation:

Engineers find problems in the world, and then they find solutions for them.

8 0
3 years ago
What type of spring is mounted on a mcpherson strut suspension system?
AysviL [449]

Answer:

Coil Spring

Explanation:

6 0
2 years ago
A heat pump operates on a vapor-compression refrigeration cycle with R-134a as the working fluid. The refrigerant enters the com
Rudiy27

Answer:

Hello your question has some missing information below are the missing information

The refrigerant enters the compressor as saturated vapor at 140kPa Determine The coefficient of performance of this heat pump

answer : 2.49

Explanation:

For  vapor-compression refrigeration cycle

P1 = P4  ; P1 = 140 kPa

P2( pressure at inlet ) = P3 ( pressure at outlet ) ; P2 = 800 kPa

<u>From pressure table of R 134a refrigerant</u>

h1 ( enthalpy of saturated vapor at 140kPa ) = 239.16 kJ/kg

h2 ( enthalpy of saturated liquid at P2 = 800 kPa and t = 60°C )

= 296.8kJ/kg

h3 ( enthalpy of saturated liquid at P3 = 800 kPa ) = 95.47 kJ/kg

also h4 = 95.47 kJ/kg

To determine the coefficient of performance  

Cop = ( h1 - h4 ) / ( h2 - h1 )

∴ Cop = 2.49

3 0
3 years ago
Other questions:
  • Amanda and Tyler opened a business that specializes in shipping liquids, such as milk, juice, and water, in cylindrical containe
    5·1 answer
  • Which solution causes cells to shrink
    13·1 answer
  • A furnace wall consisting of 0.25 m of fire clay brick, 0.20 m of kaolin, and a 0.10‐m outer layer of masonry brick is exposed t
    8·1 answer
  • The air contained in a room loses heat to the surroundings at a rate of 60 kJ/min while work is supplied to the room by computer
    7·2 answers
  • (Practice work, not graded)
    11·1 answer
  • Nitrogen can be liquefied using a Joule-Thomson expansioni process. This is done by rapidlyl and adiabatically expandign cold ni
    15·1 answer
  • In a typical transmission line, the current I is very small and the voltage V is very large. A unit length of the line has resis
    8·1 answer
  • A block of ice weighing 20 lb is taken from the freezer where it was stored at -15"F. How many Btu of heat will be required to c
    15·1 answer
  • The sports car has a weight of 4900 lblb and center of gravity at GG. If it starts from rest it causes the rear wheels to slip a
    13·1 answer
  • How can goal setting help with academic performance?
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!