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erastovalidia [21]
3 years ago
8

Which best describes cosmic microwave background radiation? radiation thought to exist but not yet measured radiation predicted

to exist in millions of years radiation that existed before the big bang leftover radiation from the big bang
Physics
1 answer:
grigory [225]3 years ago
8 0

Answer:  leftover radiation from the big bang

Microwave background radiation is a form of electromagnetic radiation that is present in the whole universe and completely fills it.

Its frequency belongs to the microwaves range and is one of the main demonstrations of the of the Big Bang theory model.

It is important to note the Big Bang occurred 400,000 years before the events related to the microwave cosmic radiation, this means the Big Bang occurred first.

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What is it called when data are arranged in rows and columns?
Tpy6a [65]

Answer:

C. Table

<h2>What is a Database table?</h2>

A organized collection of records is called a database table. The main key that uniquely identifies each row in the table. Since no two rows may have the same instantaneous value thanks to a unique key, it is simple to choose a row by its main key. A table can also contain several columns, each of which can hold a distinct kind of data. The information stored is verified using the column name and data type.  

The table name is the linguistic component of a database table. It can represent expressions or variable items, and it must be typed exactly. Square brackets denote a need for the item, whereas curly braces denote an optional element. An alternate choice is indicated by a vertical bar. A main key is a single field, and a secondary key might be a combination of many fields. This kind of information is crucial.

Any field in the data table can be referenced by the secondary key. A database's data field may be a string, a number, a date, or a time. A table's first field should always be the main key, followed by any foreign keys. Actual data should never be present in a primary key. Since the immediate key value is derived from external sources, it is crucial to use it properly. Otherwise, data input mistakes may occur.

The information kept in the database table is referred to as a secondary key. This kind is a primary key, which implies it is a secondary key. A primary key can be used as an alternate key to distinguish between different records in a table and to uniquely identify a record inside a database. Multiple fields that can be either main or alternative make up a composite key.

Depending on the type of data being stored and its intended use, a database table may have a single row or several. The main key determines the number of rows, which might be 50 or more. A secondary key can be used to establish connections between various tables and to distinguish between various data types in a database. A data table also includes a secondary key, which is essential for data retrieval and is separate from the primary key.

You can have local or global database tables. The two types of tables differ in terms of names, availability, and visibility. A global table is accessible to all users and may be utilized by any other user, while a local table is only visible to the present user. It is distinct from a typical table and requires more effort to build than a straightforward one does. Its main function is to maintain a database and store data.

Rows in a database table can be of any size. A table's rows can include any number of columns. A database table's rows can be arranged in any way. The number of rows on a data page might range from one to thousands. Each row may consist of a clustered index, a row, or both. A list of columns may also be present in a row. A clustered index can only contain information in a particular sequence.

A table can be set up in  two different ways. The information-containing row of data is its main key. The data column that contains the values for a row is known as a secondary key. A database that employs rows is the third form of table. Multiple primary keys are possible for a data row, and a secondary key is a secondary key that refers to a row column. A database will have a foreign key if it is formed with a single primary key.

There is no limit to the amount of rows and columns in a database table. Up to 1,024 rows are allowed in a typical user-defined table. The server's storage capacity determines how many rows can fit in a database table. A table can have characteristics added to it in addition to the column and row. A restriction can stop a row from having empty fields. The connection between two tables can be established via an important control.

8 0
2 years ago
Read 2 more answers
A scientist notices that an oil slick floating on water when viewed from above has many different rainbow colors reflecting off
Semenov [28]

Answer:

Explanation:

In case of oil slick a thin layer of oil is formed on water . This thin layer creates a rainbow of colour . The phenomenon is due to interference of light waves , one reflected from the upper surface of oil and the other reflected from the lower surface of the oil.

For formation of bright colour

2 μ t = ( 2n + 1 ) λ / 2

μ is refractive index of oil ,  t is thickness of oil layer  λ is wave length of light falling on the layer .

given μ = 1.2 ,   λ = 750 x 10⁻⁹   ,

2 x 1.2 t = ( 2n + 1 ) 750 x 10⁻⁹ / 2

For minimum thickness n = 0

2.4 t = 375 x 10⁻⁹

t = 156.25 n m

B ) If the refractive index of layer of medium below oil is less than that of oil , the condition of formation of colour changes

The new condition is

2 μ t = n λ

2  x 1.5 t  = 750 nm ,         n = 1 for minimum wavelength .

t = 250 nm

C ) Light mostly transmitted means dark spot is formed at that point .

For that to be observed from water side , the condition is

2 μ t = ( 2n + 1 ) λ / 2

λ = 4μ t / ( 2n + 1 )

For maximum wavelength n = 0

λ = 4μ t

= 4 x 1.5 x 200 nm

= 1200 nm .

3 0
3 years ago
Estimate the inductance L of a coil that is 12 cm long, made of about 235 copper-wire turns and a diameter of about 1.7 cm. Show
ANTONII [103]

Answer:

Inductance as calculated is 13.12 mH

Solution:

As per the question:

Length of the coil, l = 12 cm = 0.12 m

Diameter, d = 1.7 cm = 0.017 m

No. of turns, N = 235

Now,

Area of cross-section of the wire, A = \frac{\pi d^{2}}{4} = \frac{\pi \times 0.017^{2}}{4} = 2.269\times 10^{- 4}\ m^{2}

We know that the inductance of the coil is given by the formula:

L = \frac{mu_{o}AN^{2}}{l} = \frac{4\pi \times 10^{- 7}\times 2.269\times 10^{- 4}\times 235^{2}}{0.12} = 1.312\times 10^{- 4}\ H = 13.12\ mH

4 0
3 years ago
What process is used to release energy in nuclear power plants
Anika [276]
.........Nucler fission.... .
5 0
3 years ago
Read 2 more answers
Choose the four major environmental
creativ13 [48]
B that’s the answer your welcome
6 0
3 years ago
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