Alternating current flows in___ direction(s) and direct current flows in__

The closed tank of a fire engine is partly filled with water, the air space above being under pressure. A 6 cm bore connected to

skelet666 [1.2K]

Answer:

The air pressure in the tank is 53.9 $kN/m^{2}$

Solution:

As per the question:

Discharge rate, Q = 20 litres/ sec = $0.02\ m^{3}/s$

(Since, 1 litre = $10^{-3} m^{3}$ )

Diameter of the bore, d = 6 cm = 0.06 m

Head loss due to friction, $H_{loss} = 45 cm = 0.45\ m$

Height, $h_{roof} = 2.5\ m$

Now,

The velocity in the bore is given by:

$v = \frac{Q}{\pi (\frac{d}{2})^{2}}$

$v = \frac{0.02}{\pi (\frac{0.06}{2})^{2}} = 7.07\ m/s$

Now, using Bernoulli's eqn:

$\frac{P}{\rho g} + \frac{v^{2}}{2g} + h = k$ (1)

The velocity head is given by:

$\frac{v_{roof}^{2}}{2g} = \frac{7.07^{2}}{2\times 9.8} = 2.553$

Now, by using energy conservation on the surface of water on the roof and that in the tank :

$\frac{P_{tank}}{\rho g} + \frac{v_{tank}^{2}}{2g} + h_{tank} = \frac{P_{roof}}{\rho g} + \frac{v_{tank}^{2}}{2g} + h_{roof} + H_{loss}$

$\frac{P_{tank}}{\rho g} + 0 + 0 = \0 + 2.553 + 2.5 + 0.45$

$P_{tank} = 5.5\times \rho \times g$

$P_{tank} = 5.5\times 1\times 9.8 = 53.9\ kN/m^{2}$

4 0

3 years ago

According to Moore and Marra's (2005) case study, which observed two online courses, students in the first course implemented a

Archy [21]

Your question is incomplete, please let me assume this to be your complete question;

ORIGINAL SOURCE:

When instructors are creating discussion board activities for online courses, at least two questions must be answered. First, what is the objective of the discussions? Different objectives might be to create a "social presence" among students so that they do not feel isolated, to ask questions regarding assignments or topics, or to determine if students understand a topic by having them analyze and evaluate contextual situations. Based on the response to this question, different rules might be implemented to focus on the quality of the interaction more so than the quantity. The second question is, how important is online discussions in comparison to the other activities that students will perform? This question alludes to the amount of participation that instructors expect from students in online discussions along with the other required activities for the course. If a small percentage of student effort is designated for class participation, our results show that it can affect the quality and quantity of interactions.

References:

Moore, J. L., & Marra, R. M. (2005) A comparative analysis of online discussion participation protocols.Journal of Research on Technology in Education, 38(2), 191-212.

STUDENT VERSION:

According to Moore and Marra's (2005) case study, which observed two online courses, students in the first course implemented a constructive argumentation approach while students in second course had less structure for their postings. As they stated, when instructors create online discussion board activities, they must answer at least two questions. These questions are: "What is the objective of the discussions?" And "How important are online discussions in comparison to the other activities that students will perform?". According to their findings, the discussion activities that were designed based on the answers to these questions can influence the quality and quantity of interactions (Moore & Marra, 2005).

References:

Moore, J. L., & Marra, R. M. (2005) A comparative analysis of online discussion participation protocols.Journal of Research on Technology in Education, 38(2), 191-212.

Which of the following is true for the students work;

Word-for-word plagiarism

Paraphrasing plagiarism

Not Plagiarism

ANSWER: IT IS NOT PLAGIARISM

Explanation: plagiarism is the act of extracting knowledge from someone's literature work, without acknowledging the literature work. In other words, this can be called a theft of knowledge, because when you failed to acknowledge the literature source that helped you to produce your paper work, it means you have claimed to be the original owner of that knowledge.

This is not a Plagiarism because the student has acknowledged the source of the knowledge in it's literature work. The original source and the student has cited the same literature work, this why their work looks similar but not exactly the same. So the student has not committed Plagiarism

4 0

4 years ago

Thermal energy is...

Yuki888 [10]

B because thermal has to do with temperature and it’s the amount of kinetic and potential energy in and object

4 0

3 years ago

Read 2 more answers

How to write a 5bit register if a series is moved to the shift register from left to right

mr_godi [17]

The Bidirectional Shift Register is the shift register that allows one to write a 5bit register if the series is shifted from left to right.

<h3>What is a value of a 5-bit register?</h3>

A 5-bit register is valuable because it can represent up to 32 items. It is to be noted that a bit is a digit that is binary that is indicative of two states.

While a 5-bit register can have a possible number of 32 values,

6 can hold 64;
7 can hold 128;
8 can hold 256 etc.

Learn more about registers at;
brainly.com/question/19091159
#SPJ1

8 0

2 years ago

Consider a system having p processes, where each process needs a maximum of m instances of resource type R1. Given that there ar

Genrish500 [490]

Answer:

Consider a system consisting of 4 resources of same type that are share by 3 processes each of which needs at most two resources.Now we will show that the system is deadlock free.

If the system is deadlocked, it implies that each process is holding one resource and is waiting for one more. Since there are 3 processes and 4 resources, one process must be able to obtain two resources. This process requires no more resources and therefore it will return its resources when done.

Consider a system with m resources of same type being shared by n processes. Resources can be requested and released by processes only on at a time. The system is deadlock free if and only if The sum of all max needs is < m+n .

We can understand the notion of a deadlock from the following simple real-life example.To be able to write a letter one needs a letter pad and a pen. Suppose there in one letterpad and one pen on a table with two persons seated around the table. We shall identify these two persons as Mr. A and Ms. B. Both Mr. A and Ms. B are desirous of writing a letter. So both try to acquire the resources they need. Suppose Mr. A was able to get the letter pad. In the meantime, Ms. B was able to grab the pen. Note that each of them has one of the two resources they need to proceed to write a letter. If they hold on to the resource they possess and await the release of the resource by the other, then neither of them can proceed. They are deadlocked. We can transcribe this example for processes seeking resources to proceed with their execution. Consider an example in which process P1 needs three resources r1 ; r2, and r3 before it can make any further progress. Similarly, process P2 needs two resources r2 and r3 Also, let us assume that these resources are such that once granted, the permission to use is not withdrawn till the processes release these resources. The processes proceed to acquire these resources. Suppose process P1 gets resources r1 and r3 and process P2 is able to get resource r2 only. Now we have a situation in which process P1 is waiting for process P2 to release r2 before it can proceed. Similarly, process P2is waiting for process P1 to release resource r3 before it can proceed. Clearly, this situation can be recognized as a deadlock condition as neither process P1 nor process P2 can make progress. Formally, a deadlock is a condition that may involve two or more processes in a state such that each is waiting for release of a resource which is currently held by some other process.

5 0

3 years ago

Alternating current flows in___ direction(s) and direct current flows in___direction(s)

Alternating current flows in_ direction(s) and direct current flows in_direction(s)