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3 years ago

The universe is sometimes described as an isolated system. Why?

1 answer:

8 0

Answer and Explanation :The universe means it includes everything, even the things which we can not see is an isolated system because universe has no surroundings. an isolated system does not exchange energy or matter with its surroundings.Sometime universe is treated as isolated system because it obtains lots of energy from the sun but the exchange of matter or energy with outside is almost zero.

the total energy of an isolated system is always constant means total energy of universe is also constant
there is no exchange of matter or energy in an isolated system

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Diffusion of Ammonia in an Aqueous Solution Ammonia (A)-water (B) solution ta 278 K and 4 mm thick is in contact with an organic

Tom [10]

Answer:

Explanation:

The pictures below shows the whole explanation for the problem

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3 years ago

In javaWrite a program that simulates flipping a coin to make decisions. The input is how many decisions are needed, and the out

Pavel [41]

Answer:

// Program is written in Java Programming Language

// Comments are used for explanatory purpose

import java.util.*;

public class FlipCoin

{

public static void main(String[] args)

{

// Declare Scanner

Scanner input = new Scanner (System.in);

int flips;

// Prompt to enter number of toss or flips

System.out.print("Number of Flips: ");

flips = input.nextInt();

if (flips > 0)

{

HeadsOrTails();

}

public static String HeadsOrTails(Random rand)

{

// Simulate the coin tosses.

for (int count = 0; count < flips; count++)

{

rand = new Random();

if (rand.nextInt(2) == 0) {

System.out.println("Tails"); }

else {

System.out.println("Heads"); }

rand = 0;

}

7 0

3 years ago

(3) Calculate the heat flux through a sheet of brass 7.5 mm (0.30 in.) thick if the temperatures at the two faces are 150°Cand 5

bezimeni [28]

Answer:

a.) 1.453MW/m2, b.) 2,477,933.33 BTU/hr c.) 22,733.33 BTU/hr d.) 1,238,966.67 BTU/hr

Explanation:

Heat flux is the rate at which thermal (heat) energy is transferred per unit surface area. It is measured in W/m2

Heat transfer(loss or gain) is unit of energy per unit time. It is measured in W or BTU/hr

1W = 3.41 BTU/hr

Given parameters:

thickness, t = 7.5mm = 7.5/1000 = 0.0075m

Temperatures 150 C = 150 + 273 = 423 K

50 C = 50 + 273 = 323 K

Temperature difference, T = 423 - 323 = 100 K

We are assuming steady heat flow;

a.) Heat flux, Q" = kT/t

K= thermal conductivity of the material

The thermal conductivity of brass, k = 109.0 W/m.K

Heat flux, $Q" = \frac{109 * 100}{0.0075} = 1,453,333.33 W/m^{2} \\ Heat flux, Q" = 1.453MW/m^{2} \\$

b.) Area of sheet, A = 0.5m2

Heat loss, Q = kAT/t

Heat loss, $Q = \frac{109*0.5*100}{0.0075} = 726,666.667W$

Heat loss, Q = 726,666.667 * 3.41 = 2,477,933.33 BTU/hr

c.) Material is now given as soda lime glass.

Thermal conductivity of soda lime glass, k is approximately 1W/m.K

Heat loss, $Q=\frac{1*0.5*100}{0.0075} = 6,666.67W$

Heat loss, Q = 6,666.67 * 3.41 = 22,733.33 BTU/hr

d.) Thickness, t is given as 15mm = 15/1000 = 0.015m

Heat loss, $Q=\frac{109*0.5*100}{0.015} =363,333.33W$

Heat loss, Q = 363,333.33 * 3.41 = 1,238,966.67 BTU/hr

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2 years ago

One who waits too long to complain has indicated satisfaction with the agreement despite the initial lack of true consent is the

katovenus [111]

Answer: Doctrine of ratification

Explanation:Doctrine of ratification tries to show that a person who is taking so much a time to complain has indicated that he agrees even if he doesn't without a written consent. This is to eliminate undue waste of time in business, legal an other proceedings requiring consent of both parties.

Doctrine of ratification can either be implied or expressed

Implied ratification is the type of ratification where a persons actions or body language can be seen that he has accepted.

Express ratification is a ratification where a person intentionally accept by showing either through written or verbally.

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2 years ago

What are the factors that influence the power input to the compressor?

Lena [83]

Answer:

option e is correct answer

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2 years ago