Questions
Four kilograms of steam in a piston/cylinder device at 400 kPa and 175 °C undergoes isothermal...

Four kilograms of steam in a piston/cylinder device at 400 kPa and 175 °C undergoes isothermal and mechanically reversible process to a final pressure such that the steam is completely condensed (i.e., became a saturated liquid). Determine Q and W for this process:
(b) Using generalized correlations and Equations (6.70 – 6.74). Comment on the accuracy of your answer.
[Answer: Q = -9,461 kJ, W = 1494.9 kJ]

In: Other

One-quarter kilogram of air is compressed in a piston-cylinder device from 350 K and 150 kPa...

One-quarter kilogram of air is compressed in a piston-cylinder device from 350 K and 150 kPa to 550 K and 900 kPa. Determine

a. The entropy change, in KJ/K.

b. The direction of any heat transfer by using the entropy balance.

c. What-if scenario: If this process occurs adiabatically, is this process reversible, irreversible, or impossible process? Please answer the nature of this process and why.

In: Mechanical Engineering

14.2 A 0.50 L container is initially filled with Nitrogen gas at STP. The gas expands...

14.2 A 0.50 L container is initially filled with Nitrogen gas at STP. The gas expands against a piston adiabatically to a volume of 50.0% larger than the original volume. The Nitrogen may be treated as an ideal gas with ?=7/5.

a) Calculate the final temperature and pressure.

b) What is the work done?

c) Sketcha pV-diagram for this process. On this diagram also draw the isotherms for the initial and final temperatures.

In: Physics

An Insulated piston cylinder device contains 4 L of saturated liquid water at a constant pressure...

An Insulated piston cylinder device contains 4 L of saturated liquid water at a constant pressure of 150 K PA. water is stirred by a paddle wheel while a current of 9 A flows for one hour through a resistor placed in the water. if 80% of the liquid is vaporized doing this constant pressure process and the paddle does 400 kJ of work during this time. determine the resistance of the resistor?

In: Physics

A piston‑cylinder device initially contains 0.2 m3 of helium at 100 kPa and 25C. The helium...

A piston‑cylinder device initially contains 0.2 m3 of helium at 100 kPa and 25C. The helium is then compressed during a polytropic process (Pvn = constant). The final pressure is 270 kPa and the final temperature is 150C. Determine (a) the mass of the helium (kg), (b) the final volume (m3), (c) the poly tropic exponent n, (d) the work for the compression process (kJ), and (e) the heat transfer (kJ).

In: Mechanical Engineering

Four numbers are selected without replacement from {1,2,3,4,5,6,7} to form a 4-digit number. What is the...

Four numbers are selected without replacement from {1,2,3,4,5,6,7} to form a 4-digit number. What is the probability that the number is greater than 6543?

In: Math

Identifying the highest energy form of adenosine

 Identifying the highest energy form of adenosine 

Select the highest energy form of adenosine from the following images.

In: Chemistry

which stocks are the highest yielding to invest in?

which stocks are the highest yielding to invest in?

In: Economics

The Powerball is a lottery sold in Arizona, Connecticut, Delaware, District of Columbia, Idaho, Indiana, Iowa,...

The Powerball is a lottery sold in Arizona, Connecticut, Delaware, District of Columbia, Idaho, Indiana, Iowa, Kansas, Kentucky, Louisiana, Minnesota, Missouri, Montana, Nebraska, New Hampshire, New Mexico, Oregon, Rhode Island, South Dakota, West Virginia, and Wisconsin. It was introduced in April of 1992 and took its present form in November of 1997.

     Although the Powerball is a multi-state lottery game, it is not the first. That distinction goes to Lotto*America, which was created in 1988 when Iowa and six other states joined forces to offer a game with a large jackpot. Since the more people that play, the bigger the jackpots tend to be, multi-state lotteries offer larger prizes than those standing alone.

     A Powerball jackpot starts at $10 million and grows if no one wins it. Since, as we will see, the chance of winning a jackpot is small, the jackpot often grows to huge amounts, sometimes around $300 million. In case there are multiple winners, the jackpot is divided equally among them. Drawings take place on Wednesday and Saturday evenings at 9:59 P.M. and can be watched during the 10:00 P.M. news.

     Here is how the Powerball is played: A player first select five numbers from the numbers 1-49 and then chooses a Powerball number, which can be any number between 1 and 42. A ticket costs $1. In the drawing, five white balls are drawn randomly from 49 white balls numbered 1-49; and one red Powerball is drawn randomly from 42 red balls numbered 1-42.

     To win the jackpot, a ticket must match all of the balls drawn; there are other smaller prizes for matching some but not all of the balls drawn. What are the chances of winning the jackpot? What are the chances of winning any prize whatsoever? The following table provides the number of matches, the prizes given, and the probabilities of winning.

Matches

Prize

Probability

5+1

Jackpot

0.00000001

5

$100,000

0.00000051

4+1

$5,000

0.00000275

4

$100

0.00011262

3+1

$100

0.00011812

3

$7

0.00484285

2+1

$7

0.00165366

1+1

$4

0.00847500

0+1

$3

0.01355999

Here are some things to note about the above table.

● In the first column, an entry of the form w+1 indicates w matches out of five plus the Powerball; one of the form w indicates w matches out of five and no Powerball

● The prize amount for the jackpot depends on how recently it has been won, how many people win it, and choice of jackpot payment.  

● Each probability in the third column is given to eight decimal places.

Let E be an event having probability P. It can be shown that in independent repetitions of the experiment, it takes on the average times until event E occurs. We will apply this fact to the Powerball.

Suppose we were to purchase one Powerball ticket per week. Let’s find how long we should expect to wait before winning the jackpot. The third column of the above table shows that for the jackpot, P=0.00000001 and, therefore, we have 1/ 0.00000001 = 100,000,000. So, if we purchased one Powerball ticket per week, then we should expect to wait approximately 100 million weeks or roughly 1.92 million years, before winning the jackpot.

  1. If you purchase one ticket, what is the probability that you win a prize? (1 mark)
  2. If you purchase one ticket, what is the probability that you don’t win a prize? (1 mark)
  3. If you win a prize, what is the probability it is the $3 prize for having only the Powerball number?
  4. If you were to buy one ticket per week, approximately how long should you expect to wait before getting a ticket with exactly three winning numbers and no Powerball?
  5. If you were to buy one ticket per week, approximately how long should you expect to wait before winning a prize? (1 mark)

In: Statistics and Probability

52 cards in a deck choose 5 What is the probability of choosing 4 kings and...

52 cards in a deck choose 5

What is the probability of choosing 4 kings and one other card.

what is the probability of choosing one king and 4 other cards with the same number?

In: Statistics and Probability