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I think that is C ?
If an astronomer was to look through a telescope and notice that a star's emitted light had a slightly red tint to it, compared to what the emitted light should be. What would that mean about that star?
Answer:
In the chapters that follow, we will provide the temperature of the stars we are describing, and this section tells you how those temperatures are determined from the colors of light the stars give off. Hubble Space Telescope image of the Sagittarius Star Cloud. The image shows many stars of various colors, white, blue, red and yellow spread over a black background. The most common star colors in this image are red and yellow. Figure 1: Sagittarius Star Cloud. This image, which was taken by the Hubble Space Telescope, shows stars in the direction toward the center of the Milky Way Galaxy. The bright stars glitter like colored jewels on a black velvet background. The color of a star indicates its temperature. Blue-white stars are much hotter than the Sun, whereas red stars are cooler. On average, the stars in this field are at a distance of about 25,000 light-years (which means it takes light 25,000 years to traverse the distance from them to us) and the width of the field is about 13.3 light-years. (credit: Hubble Heritage Team (AURA/STScI/NASA))
Color and Temperature
As we learned in The Electromagnetic Spectrum section, Wien’s law relates stellar color to stellar temperature. Blue colors dominate the visible light output of very hot stars (with much additional radiation in the ultraviolet). On the other hand, cool stars emit most of their visible light energy at red wavelengths (with more radiation coming off in the infrared) (Table 1). The color of a star therefore provides a measure of its intrinsic or true surface temperature (apart from the effects of reddening by interstellar dust, which will be discussed in Between the Stars: Gas and Dust in Space). Color does not depend on the distance to the object. This should be familiar to you from everyday experience. The color of a traffic signal, for example, appears the same no matter how far away it is. If we could somehow take a star, observe it, and then move it much farther away, its apparent brightness (magnitude) would change. But this change in brightness is the same for all wavelengths, and so its color would remain the same. Table 1. Example Star Colors and Corresponding Approximate Temperatures
Star Color Approximate Temperature Example
Blue 25,000 K Spica
White 10,000 K Vega
Yellow 6000 K Sun
Orange 4000 K Aldebaran
Red 3000 K Betelgeuse
Go to this interactive simulation from the University of Colorado to see the color of a star changing as the temperature is changed. The hottest stars have temperatures of over 40,000 K, and the coolest stars have temperatures of about 2000 K. Our Sun’s surface temperature is about 6000 K; its peak wavelength color is a slightly greenish-yellow. In space, the Sun would look white, shining with about equal amounts of reddish and bluish wavelengths of light. It looks somewhat yellow as seen from Earth’s surface because our planet’s nitrogen molecules scatter some of the shorter (i.e., blue) wavelengths out of the beams of sunlight that reach us, leaving more long wavelength light behind. This also explains why the sky is blue: the blue sky is sunlight scattered by Earth’s atmosphere.
Color Indices
In order to specify the exact color of a star, astronomers normally measure a star’s apparent brightness through filters, each of which transmits only the light from a particular narrow band of wavelengths (colors). A crude example of a filter in everyday life is a green-colored, plastic, soft drink bottle, which, when held in front of your eyes, lets only the green colors of light through. One commonly used set of filters in astronomy measures stellar brightness at three wavelengths corresponding to ultraviolet, blue, and yellow light. The filters are named: U (ultraviolet), B (blue), and V (visual, for yellow). These filters transmit light near the wavelengths of 360 nanometers (nm), 420 nm, and 540 nm, respectively. The brightness measured through each filter is usually expressed in magnitudes. The difference between any two of these magnitudes—say, between the blue and the visual magnitudes (B–V)—is called a color index. By agreement among astronomers, the ultraviolet, blue, and visual magnitudes of the UBV system are adjusted to give a color index of 0 to a star with a surface temperature of about 10,000 K, such as Vega. The B–V color indexes of stars range from −0.4 for the bluest stars, with temperatures of about 40,000 K, to +2.0 for the reddest stars, with temperatures of about 2000 K. The B–V index for the Sun is about +0.65. Note that, by convention, the B–V index is always the “bluer” minus the “redder” color. Why use a color index if it ultimately implies temperature? Because the brightness of a star through a filter is what astronomers actually measure, and we are always more comfortable when our statements have to do with measurable quantities.
Explanation:yw :P
How many moles would 9.02 x 10^25 molecules of HCI equal?
Answer:
The answer is 149.83 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question
N = 9.02 × 10^25 molecules of HCI
We have
[tex]n = \frac{9.02 \times {10}^{25} }{6.02 \times {10}^{23} } \\ = 149.83388704...[/tex]
We have the final answer as
149.83 molesHope this helps you
PLS HELP:)Which situation will cause a stationary object to start moving?
A. A net force greater than 0
B. Balanced forces
C. A net force equal to 0
D. Two forces that cancel each other out
Zn + 2HCl--------------> Zn Cl2 + H2
This is ______________________ kind of reaction.
Answer:
Single displacement (Substitution)
Explanation:
A pot of water is heated on a gas-flame stove and begins to boil. Which two
transfers of thermal energy involved in this system are examples of radiation?
A. From the burner to a nearby spoon
B. In the surrounding air as air currents develop
I C. From the burner to air that is not touching it
D. From the water to the air
Answer:
a.) & d.)
Explanation:
It should ideally go from Mechanical, Electrical, thermal, light then chemical. I attached a similar example to better explain it.
The two transfers of thermal energy involved in this system are examples of radiation are From the burner to a nearby spoon and From the water to the air Hence, option a & d are correct
What is Heat Transfer ?
Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy between physical systems.
Heat transfer is classified into various mechanisms, such as thermal conduction, thermal convection, thermal radiation, and transfer of energy by phase changes.
According to given question, Energy should ideally go from Mechanical, Electrical, thermal, light then chemical.
Therefore, The two transfers of thermal energy involved in this system are examples of radiation are From the burner to a nearby spoon and From the water to the air Hence, option a & d are correct
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In humans, the allele for curly hair and the allele for straight hair show incomplete dominance the offspring of a curly haired person and a straight haired person will have A) Curly hair B) straight hair C) wavy hair D) Curly and straight hair
Answer:
A
Explanation:
Curly Hair
Which substances form a due to chemical reaction?
A.Mass
B.Products
C.Atoms
D.Reactants
Answer:
B. Products
Explanation:
trust me its right
All isotopes of sodium (Na) must have,
Answer:
11 protons and 11 electrons.
Explanation:
Na is a neutral element and element number 11.
This means that it has 11 protons and 11 electrons.
In order to create an isotope, you would add or get rid of neutrons to get different mass numbers but the same element. The number of protons and electrons would remain the same.
Directions: The diagram below shows Earth's orbit around the Sun. Use the diagram and
your knowledge of science to answer any questions that follow.
SL
SK
2
Expectation: 8.7(A)
At what position is it spring in the Northern Hemisphere?
Position
(6) Position K
© Position L
D Position M
Answer:
i think its k.
Explanation:
position k im sure
what are two transition metals that start with the letter R
Answer:
Ruthenium and Rhodium
Explanation:
Please help, and can you tell, if some my answers are correct?
what is the mass of 9.6 x10^23 atoms of iron?
According to the Avogadro's number, the mass of 9.6 x 10²³ atoms of iron is 89.002 g.
What is Avogadro's number?Avogadro's number is defined as a proportionality factor which relates number of constituent particles with the amount of substance which is present in the sample.
It has a SI unit of reciprocal mole whose numeric value is expressed in reciprocal mole which is a dimensionless number and is called as Avogadro's constant.It relates the volume of a substance with it's average volume occupied by one of it's particles .
According to the definitions, Avogadro's number depend on determined value of mass of one atom of those elements.It bridges the gap between macroscopic and microscopic world by relating amount of substance with number of particles.
Number of atoms can be calculated using Avogadro's number as follows: mass/molar mass×Avogadro's number
Therefore,mass=9.6×10²³×55.84/6.023×10²³=89.002 g
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(PLS HELP!) Explain the layout of the modern periodic table, including rows, columns, groups, and blocks. Be sure to explain what’s in each part of the periodic table.
Answer: The rows of the periodic table represent the highest energy level of that element.
The columns represent how many valence electrons that element has.
Groups are the same thing as columns, they represent how many valence electrons am element has.
The blocks of the periodic table represent what sublevel(s) the valence electrons fill.
Explanation: Yes
Answer:
I can help!
Explanation:
Blocks
Atomic symbol is the one- or two-letter symbol for each element.
Atomic number is the number of protons in the nucleus, which determines the order of elements on the periodic table. This is also the total number of electrons in neutral atoms of the element.
Atomic mass is the mass in grams of 1 mole of atoms. Note that 1 mole contains 6.022·1023 atoms.
Groups
The first two groups of the periodic table(Alkali metals and Alkali Earth metals) are the s-block. Note that helium, in the last column of the table, is also part of the s-block. The outermost electrons of these elements are in s orbitals.
The transition metals make up the d-block, with electrons filling d orbitals. The lanthanides and actinides make up the f-block, with electrons filling f orbitals.
Groups 13 through 18,(post transition metals, metalloids, Reactive nonmetals, and Noble gases-)except for helium, make up the p-block. The outermost electrons of these elements are in p orbitals.
Sections
Metals are more likely to lose valence electrons
nonmetals are more likely to accept electrons.
Metalloids may act like metals or nonmetals, either losing or gaining valence electrons depending on the situation.
Transition metals(groups 3-12) behave somewhat differently because they can lose electrons from their outermost s or d orbitals.
Noble gases are the elements in group 18 that don’t tend to react with other elements. Noble gases have completely filled outer electron shells, as you can see because they’re at the end of each period. The electrons in these elements are stable, making the elements unreactive.
Periods and Groups
Groups of elements have similar properties in terms of how they react with other elements.
All elements in a row have the same number of electron shells. Each next element in a period has one more proton and is less metallic than its predecessor.
Hope this helps!!
Make a suggestion on how you will deal with the problem
Answer:
is it a research work?
Explanation:
if it is first u write about what is a climate what r due to climatic changes
Answer:
《<☆HOPE IT WILL HELP YOU 》>☆
Explanation:
Dealing with the problem by
Never lose your hope you're cofidance your power
Always take dlessing or suggeation from the elder or your parent
•●○Please mark my ans as BRAIN LIST○●•
What do you think is the difference between a scientific theory and law?
Answer:
A scientific theory predicts why something might happen and when more information goes into the theory it can better predict. But a law is something that no matter what will always be true.
Explanation:
Potassium hydroxide (KOH) reacts with sulfuric acid (H2SO4) to produce potassium sulfate (K2SO4) and water (04.03 MC)
Answer: A double replacement because potassium ions bond with sulfate ions to form a salt
Explanation:
What is 0.55 hectometers expressed in decimeters?
a.
550 dm
b.
5.5 dm
c.
55 dm
d.
0.00055 dm
Answer:
a. 550 dm
Explanation:
Alveolar air (a mixture of nitrogen, oxygen, and carbon dioxide) has a total pressure of 0.998 atm. If the partial pressure of oxygen gas is 0.198 atm and the partial pressure of nitrogen gas is 0.770 atm, what is the partial pressure of carbon dioxide in millimeters of mercury?
Answer:
The partial pressure of carbon dioxide is 22.8 mmHg
Explanation:
Dalton's Law is a gas law that relates the partial pressures of the gases in a mixture. This law says that the pressure of a gas mixture is equal to the sum of the partial pressures of all the gases present.
In this case:
Ptotal=Pnitrogen + Poxygen + Pcarbondioxide
You know that:
Ptotal= 0.998 atmPnitrogen= 0.770 atmPoxygen= 0.198 atmPcarbondioxide= ?Replacing:
0.998 atm=0.770 atm + 0.198 atm + Pcarbondioxide
Solving:
Pcarbondioxide= 0.998 atm - 0.770 atm - 0.198 atm
Pcarbondioxide= 0.03 atm
Now you apply the following rule of three: if 1 atm equals 760 mmHg, 0.03 atm how many mmHg equals?
[tex]Pcarbondioxide=\frac{0.03 atm*760 mmHg}{1 atm}[/tex]
Pcarbondioxide= 22.8 mmHg
The partial pressure of carbon dioxide is 22.8 mmHg
Suppose a deep sea diver dives from the surface to 81 feet below the surface. He then dives down 13 more feet.
Find and interpret the sum to describe the diver's present depth.
Answer:
-94 feet.
Explanation:
the chemical formula 4N2O has how many atoms of each element?
Answer:
8;1
Explanation:
eight nitrogen and one oxygen
Give two differences between the properties of iron and sodium
Answer:
Iron have 26 atomic and sodium have 11 atomic
Explanation:
The sodium is a non-transition metal. Its melting point is low and boiling points and is a soft metal, whereas iron is a transition metal with very high melting and boiling points, It is a hard metal.
What is transition metal ?The term transition metal is defined as any of various metallic elements such as chromium, iron, and nickel that have valence electrons in two shells instead of only one.
Between the s-block and p-block elements in the periodic table are transition metals. As a result, they are known as d-block elements.
Sodium is soft, has a much lower melting point than water, and reacts with it violently, producing heat and hydrogen or even exploding. Additionally, sodium and water react to create a hazardous compound.
Thus, these are difference between the properties of sodium and iron.
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I need help on this problem. I need it answered ASAP
Use this formula: Density = Mass/Volume
Given in the question:
Mass: 10g
Volume: 5cm3
The calculations:
Density = Mass/Volume
= 10/5
= 2g/[tex]cm^{3}[/tex]
Therefore, the density will be 2g/[tex]cm^{3}[/tex]
Calculate the number of particles in a 0.75 gram sample of Calcium Nitrate; Ca(NO3)2
The number of particles : 2.75 x 10²¹
Further explanationA mole is a unit of many particles (atoms, molecules, ions) where 1 mole is the number of particles contained in a substance that is the same amount as many atoms in 12 gr C-12
1 mole = 6.02.10²³ particles
[tex]\tt n=\dfrac{N}{N_o}[/tex]
N = number of particles
No = Avogadro number (6.02.10²³)
n = number of moles
While the number of moles can also be obtained by dividing the mass (in grams) with the molar mass of element or molecule
0.75 gram sample of Calcium Nitrate; Ca(NO₃)₂
MW of Ca(NO₃)₂ : 164.09 g/mol
[tex]\tt mol~Ca(NO_3)_2=\dfrac{0.75}{164.09}=0.00457[/tex]
The number of particles
[tex]\tt N=n\times N_o\\\\N=0.00457\times 6.02\times 10^{23}=2.75\times 10^{21}[/tex]
On a mountain in the spring, snow melts and flows into a creek. Then the creek flows into a river, which eventually flows into the ocean.
1. Which part of the water cycle is this an example?
2. What forces cases the water to flow drown hill?
Answer:
I'm sorry but I need points
Divide the numbers
2
2
+
2
2
=
4
5
2
2
+
2
2
=
4
x
5
22+22=54x
1
+
2
2
=
4
5
1
+
2
2
=
4
x
5
1+22=54x
2
Divide the numbers
again
1
+
2
2
=
4
5
1
+
2
2
=
4
x
5
1+22=54x
1
+
1
=
4
5
1
+
1
=
4
x
5
1+1=54x
3
Add the numbers
1
+
1
=
4
5
1
+
1
=
4
x
5
1+1=54x
2
=
4
5
2
=
4
x
5
2=54x
4
Multiply all terms by the same value to eliminate fraction denominators
2
=
4
5
2
=
4
x
5
2=54x
5
⋅
2
=
5
⋅
4
5
5
⋅
2
=
5
⋅
4
x
5
5⋅2=5⋅54x
5
Simplify
Multiply the numbers
Cancel multiplied terms that are in the denominator
1
0
=
4
10
=
4
x
10=4x
6
Divide both sides of the equation by the same term
7
Simplify
Show less
Solution
5
2
=
Answer:
This is not a question
Explanation:
no
Which refers to the number of wavelengths that pass a fixed point in a second?
wavelength
O amplitude
frequency
O compression
Please hurry will give brainliest on 10 mins
Answer:
frequency
Explanation:
The number of wavelengths that pass through a fixed point in a second is called the frequency of the wave. It has the unit of Hertz. Hence, option C is correct.
What is frequency ?The term that refers to the number of wavelengths that pass a fixed point in a second is frequency.
Frequency is a fundamental concept in wave motion and is defined as the number of complete cycles of a wave that occur per unit time. For example, the frequency of a sound wave is measured in hertz (Hz) and is equal to the number of sound wave cycles that occur per second.
The higher the frequency of a wave, the more cycles occur in a given period of time. Wavelength, on the other hand, refers to the distance between two adjacent points on a wave that are in phase with each other, such as the distance between two crests or two troughs.
Wavelength and frequency are related, and the frequency of a wave is inversely proportional to its wavelength. As the frequency of a wave increases, its wavelength decreases.
Amplitude refers to the maximum displacement of a wave from its equilibrium position, while compression is a region in a longitudinal wave where the particles are close together. Hence, option C is correct.
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Which of the following can cause the substance to change phase? Select all that apply.
change in temperature
change of shape
change in mass
change in pressure
Answer:
a and d
Explanation:
Which type of compounds are formed by ions that have opposite charges?
A. molecules
B. covalent
C. ionic
D. metallic
Answer:
c
Explanation:
if you need explanation, ask freely
The three main types of RNA are ____________________, _____________________, and ______________.
Answer:
There are three main types of RNA: messenger RNA, ribosomal RNA, and transfer RNA.
Explanation:
Messenger RNA (mRNA), Ribosomal RNA (rRNA), and Transfer RNA (tRNA).