A(n) is a safety device commonly used with a slotted nut.

sp2606 [1]

C, being able to maintain legal information on grant programs

3 0

2 years ago

What is the air change rate (ACH) for a 100 ft^2 (9.3 m^2) space with a 10 ft (3.0 m) ceiling and an airflow rate of 200 cfm (95

kakasveta [241]

Answer:

The ACH is 12/h

Solution:

As per the question:

Area of the space, $A_{s} = 100 ft^{2}$

Height of the given space, h = 10 ft

Air flow rate, $Q_{a} = 200 cfm$

Now, to find the Air Change Rate (ACH):

We calculate the Volume of the given space:

$V_{s} = A_{s}\times h = 100\times 10 = 1000 ft^{3}$

Now, the ACH per min:

= $\frac{V_{s}}{Q_{a}} = \frac{1000}{200} = 5/min$

Now, ACH per hour:

= $\frac{60}{5} = 12/h$

3 0

3 years ago

How many grams of perchloric acid, HClO4, are contained in 37.6 g of 70.5 wt% aqueous perchloric acid? How many grams of water a

kap26 [50]

Answer :

The mass of perchloric acid is, 26.5 grams.

The mass of water in the same solution is, 11.1 grams

Explanation :

As we are given that 70.5 wt % aqueous perchloric acid that means 70.5 grams of perchloric acid present in 100 grams of solution.

Now we have to determine the mass of perchloric acid in 37.6 grams of aqueous perchloric acid.

As, 100 grams of aqueous perchloric acid (solution) contains 70.5 grams of perchloric acid.

So, 37.6 grams of aqueous perchloric acid (solution) contains $\frac{37.6}{100}\times 70.5=26.5$ grams of perchloric acid.

Thus, the mass of perchloric acid is, 26.5 grams.

Now we have to determine the mass of water are in the same solution.

Total mass of solution = 37.6 g

Mass of perchloric acid = 26.5 g

Mass of water = Total mass of solution - Mass of perchloric acid

Mass of water = 37.6 g - 26.5 g

Mass of water = 11.1 g

Thus, the mass of water in the same solution is, 11.1 grams

4 0

3 years ago

D

nadya68 [22]

Any collection of data or information that has been properly structured for quick search and retrieval by a computer is referred to as a database, often known as an electronic database.

<h3>What is electronic database?</h3>

Databases are designed to make it easy to save, retrieve, edit, and delete data while carrying out various data-processing tasks. In response to queries, a database management system (DBMS) retrieves data from the database.
Databases are briefly discussed after that. See computer science: Information systems and databases; information processing for a comprehensive explanation.
A file or collection of files used to store a database.
These files' contents can be divided up into records, each of which has one or more fields.
The fundamental units of data storage are fields, and each field typically contains data related to one feature or attribute of the thing that the database is describing.
Additionally, records are arranged into tables that contain details on the connections between their various fields.
A database in the strict sense offers cross-referencing capabilities, despite the fact that the term "database" is used broadly to refer to any collection of information in computer files.

Users can quickly search, rearrange, organize, and choose the fields in numerous records to access or produce reports on certain data aggregates using keywords and a variety of sorting instructions.

To Learn more About database Refer To :

brainly.com/question/518894

#SPJ1

5 0

1 year ago

Miller Indices:

svetlana [45]

Answer:

A) The sketches for the required planes were drawn in the first attachment [1 2 1] and the second attachment [1 2 -4].

B) The closest distance between planes are d₁₂₁=a/√6 and d₁₂₋₄=a/√21 with lattice constant a.

C) Five posible directions that electrons can move on the surface of a [1 0 0] silicon crystal are: |0 0 1|, |0 1 3|, |0 1 1|, |0 3 1| and |0 0 1|.

Compleated question:

1. Miller Indices:

a. Sketch (on separate plots) the (121) and (12-4) planes for a face centered cubic crystal structure.

b. What are the closest distances between planes (called d₁₂₁ and d₁₂₋₄)?

c. List five possible directions (using the Miller Indices) the electron can move on the surface of a (100) silicon crystal.

Explanation:

A)To draw a plane in a face centered cubic lattice, you have to follow these instructions:

1- the cube has 3 main directions called "a", "b" and "c" (as shown in the first attachment) and the planes has 3 main coeficients shown as [l m n]

2- The coordinates of that plane are written as: π:[1/a₀ 1/b₀ 1/c₀] (if one of the coordinates is 0, for example [1 1 0], c₀ is ∞, therefore that plane never cross the direction c).

3- Identify the points a₀, b₀, and c₀ at the plane that crosses this main directions and point them in the cubic cell.

4- Join the points.

In this case, for [1 2 1]:

$l=1=1/a_0 \rightarrow a_0=1$

$m=2=2/b_0 \rightarrow b_0=0.5$

$n=1=1/c_0 \rightarrow c_0=1$

for $[1 2 \overline{4}]$ :

$l=1=1/a_0 \rightarrow a_0=1$

$m=2=2/b_0 \rightarrow b_0=0.5$

$n=\overline{4}=-4/c_0 \rightarrow c_0=-0.25$

B) The closest distance between planes with the same Miller indices can be calculated as:

With $\pi:[l m n]$ ,the distance is $d_{lmn}= \displaystyle \frac{a}{\sqrt{l^2+m^2+n^2}}$ with lattice constant a.

In this case, for [1 2 1]:

$d_{121}= \displaystyle \frac{a}{\sqrt{1^2+2^2+1^2}}=\frac{a}{\sqrt{6}}=0.41a$

for $[1 2 \overline{4}]$ :

$d_{12\overline{4}}= \displaystyle \frac{a}{\sqrt{1^2+2^2+(-4)^2}}=\frac{a}{\sqrt{21}}=0.22a$

C) The possible directions that electrons can move on a surface of a crystallographic plane are the directions contain in that plane that point in the direction between nuclei. In a silicon crystal, an fcc structure, in the plane [1 0 0], we can point in the directions between the nuclei in the vertex (0 0 0) and e nuclei in each other vertex. Also, we can point in the direction between the nuclei in the vertex (0 0 0) and e nuclei in the center of the face of the adjacent crystals above and sideways. Therefore:

dir₁=|0 0 1|

dir₂=|0 0.5 1.5|≡|0 1 3|

dir₃=|0 1 1|

dir₄=|0 1.5 0.5|≡|0 3 1|

dir₅=|0 0 1|

5 0

3 years ago