Answer:
ptic fiber communication and satellite communication are the leading technologies which are revolutionizing the world of telecommunications. Both technologies have their advantages and limitations which make them suitable for certain type of applications. This article will provide an overview of optic fiber and satellite communication technologies and present a comparison of the features and related issues.
Optic Fiber Communication
Optic Fiber communication transmits information by sending pulses of light (using laser) through an optic fiber. The low signal loss in optic fibers and high data rate of transmission systems, allow signals with high data rates (exceeding several Gbps) to travel over long distances (more than 100 km) without a need of repeater or amplifier. Moreover, using wavelength division multiplexing (WDM) allows a single fiber to carry multiple signals (upto 10 different signals) of multi-Gbps transmissions. Optic Fiber communication offers extremely high bandwidth, immunity to electromagnetic interference, non-existent delays and immunity from interception by external means. In the 1980s and 1990s, the continents were linked together using undersea optic fiber bringing about a paradigm shift in the global telecommunications.
These advancements in optic fiber communication has resulted in decrease of satellite communications for several types of communications. For instance, transmission between fixed locations or point-to-point communications, where large bandwidths are required (such as transoceanic telephone systems) are made through optic fiber instead of using satellite communication. Optic Fiber communication is also used to transmit telephone signals, Internet communication, LAN (Gigabit LAN) and cable television signals.
Satellite Communication
Satellite communications use artificial satellites as relays between a transmitter and a receiver at different locations on Earth. Satellite systems allow users to bypass typical carrier offices and to broadcast information to multiple locations. Communications satellites are used for radio, TV, telephone, Internet, military and other applications. There are more than 2,000 satellites around Earth’s orbit, being used for communication by both government and private organizations.
Communication Satellites are LOS (line-of-sight) microwave systems with a repeater. These satellites rotate around the earth with the speed of earth and are known as geostationary satellites. The limitations of antenna size also limits focusing capability making the coverage for a single satellite transmitter very large. This makes satellite communication ideal for TV and radio services as the signal has to flow from a single point to many points in a single direction. The large distance of satellites from the earth (about 22,300 miles) results in delays which adversely effects two-way communication like mobile conversations. Low earth orbit satellites can be used for two-way mobile communication because less power is required to reach those satellites.
Explanation:
Which branch of chemistry would be used to make steel?
Answer:
the five major branches of chemistry are organic, inorganic, analytical, physical, and biochemistry.
Write a balanced equation describing the reduction of H2SeO4 by SO2 to produce selenium. (Use the lowest possible coefficients. Include states-of-matter under SATP conditions in your answer.)
Answer:
[tex]\mathbf{H_2SeO_{4(aq)} + 3SO_{2(aq)} + 2H_2O_{(l) } \to Se_{(s)} + 3H_2SO_{4(aq)} }[/tex]
Explanation:
We are to write a balanced equation from the information given above by including the states of their matter according to SATP conditions;
[tex]\mathbf{H_2SeO_{4(aq)} + 3SO_{2(aq)} + 2H_2O_{(l) } \to Se_{(s)} + 3H_2SO_{4(aq)} }[/tex]
From above;
The oxidizing agent is [tex]\mathbf{H_2SeO_{4(aq)} }[/tex]
The reducing agent is [tex]\mathbf{SO_{2(aq)} }[/tex]
which type of organism carries out cellular respiration
Answer:Prokaryotic cells carry out cellular respiration within the cytoplasm and eukaryotic cells carry out respiration in the mitochondria
Explanation:
HEY THIS ANSWER CORRECT ?
Answer:
I don't think that answer is right. I got 543.04 grams.
Explanation:
I think the question is asking for grams in the samlpe instead of the moles in the sample because it already gives you the amount of moles.
2 points
A student saw the Moon rise at 6:20 a.m. on Monday. If he wants to see
the Moon rise again on Tuesday, vhat time should he look in the sky?(Mark
the one best answer.)
About 6:20 am
About 6:20pm
About 5:30 am
About 7:10am
how does heat transfer into conduction
Explanation:
Heat is transferred by conduction when adjacent atoms vibrate against one another or electrons move from one atom to another . Conduction is the most significant meanings of heat transfer within a solid or between solid objects informal contact.
How many moles are in 563.9 grams of arsenic?
Answer:
No. of moles, n = 7.52 moles
Explanation:
Given that,
Mass, m = 563.9 grams
Molar mass of arsenic = 74.92 g/mol
We need to find the number of moles in 563.9 grams of arsenic. Let it is denoted by n. It is equal to given mass divided by total molar mass.
[tex]n=\dfrac{563.9 }{74.92}\\\\=7.52\ \text{moles}[/tex]
So, there are 7.52 moles in 563.9 grams of arsenic.
can you make energy with ionized particles? yes or no and how
The frequency of the stretching vibration of a bond in IR spectroscopy depends on what two quantities?
Answer:
Strength of the bond
Masses of the bonded atoms.
Explanation:
The lack of such groups means that they are not endogenous in the concentrate. 1. A bond's spreading frequency relies on the frequency of the bond and the concentrations of the atoms that are bonded.
what's the pH of a solution composed of 0.2 moles of NH3 and 0.15 moles of nh4cl
Answer:
[tex]pH=4.63[/tex]
Explanation:
Hello!
In this case, since the ionization of ammonia, which is a weak base, is written as:
[tex]NH_3+H_2O\rightleftharpoons NH_4^++OH^-[/tex]
We can see that the ammonium ion is the conjugate acid whereas the hydroxide ions the conjugate base; that is why we use the Henderson-Hasselbach equation to compute the pH, given the pKb of ammonia 4.75:
[tex]pH=pKb+log(\frac{[conj\ acid]}{[base]} )[/tex]
In such a way, for the given moles of ammonia, base, and those of ammonium chloride, conjugate acid form, we obtain:
[tex]pH=4.75+log(\frac{0.15}{0.2} )\\\\pH=4.63[/tex]
Best regards!
When a chemical change occurs _____.
Need ASAP please someone
Select one:
a. atoms are rearranged
b. the law of conservation of mass is always obeyed
c. the chemical properties of new substances are different from the ones you started with
d. all of these
Answer:
d
Explanation:
i think its d but im not sure.
Which of the following is the definition of erosion?
A the process that involves The movement Of soil and rock
The process Of disitgration Of rock and soil
Neither
Both
Choose one and explain
Answer:
Neither
Explanation:
None of the answer choices is the correct definition of erosion. Erosion is actually the removal of weathered materials and particle from the surface of rocks and soils.
The process by which rocks and soils are moved is called transportation. The process of disintegration of rocks and soil is called weathering.Erosion is a serious problem in Agriculture as it removes rich and fertile soil cover. This therefore renders the soil barren and stripped of available nutrients.
Answer:
The process of breaking down rock and soil.
Explanation:
What type of succession takes place when a community starts to grow?
A. Primary
B. Secondary
Answer:
Primary
Explanation:
Succession is a series of progressive changes in the composition of an ecological community over time. In primary succession, newly exposed or newly formed rock is colonized by living things for the first time.
Why did the French set up trading posts in North America?
Answer: Their main aim was to provide goods, specifically furs and sugar exportation.
Explanation:
Many reactions double their rates with every ten degrees rise in temperature. Assume that such a reaction takes place at 301 K and 311 K. What must its activation energy be for this statement to hold
Answer:
57.6 KJ/mol
Explanation:
We have that;
T1 = 301 K
T2= 311 K
k1 = k1
k2= 2k1
R = 8.314 JK-1
Ea= ?
So;
ln(k1/k2) = (-Ea/R) (1/T1 - 1/T2)
ln (k1/2k1) = -(Ea/8.314) (1/301 - 1/311)
ln(1/2) = -(Ea/8.314) (3.3 * 10^-3 - 3.2 * 10^-3)
-0.693 = -(Ea/8.314) 0.1 * 10^-3
-0.693/ 0.1 * 10^-3 = -(Ea/8.314)
-6930 = -(Ea/8.314)
Ea = 6930 * 8.314
Ea = 57.6 KJ/mol
Please help if you know please and thanks ;)
Answer:
it takes two hydrogen atoms for every oxygen atom to produce this reaction, so the mole ratio between hydrogen and oxygen is 2:1
A substance made up of two or more types of atoms that are NOT chemically combined is called a(n)
A
element
B
mixture
с
compound
D
pure substance
Answer:
pure substance
Explanation:
it does not combine to anything.