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## How does sun's magnetic field work?

Hunaid L. Hanfee
Featured 10 months ago

The Sun is made of charged particles, magnetic fields are created by the movement of the particles.

#### Explanation:

When charged particles move around really fast they create magnetic fields.

The Sun is made of positively charged ions and negatively charged electrons in a state of matter called plasma. In the Sun, the flows of hot plasma in the convection zone create the solar magnetic field.

The plasma is a hot gas "soup" with many free charged particles (electrons and protons). The moving charges are a current, and produce magnetic fields, just like the current in coils of wire around the nail.

The Sun's charged particles move due to the Sun's high temperature and movement of its axis.

Magnetic field of the Sun is complex because-

$1.$ Due to high temperature it causes plasma to move around. The moving plasma creates many complicated magnetic fields that twist and turn.

$2.$Solar winds also causes magnetic field.

$3.$ The plasma near the poles rotates slower than the plasma at the equator causing twisting and stretching of magnetic fields, too.

The sun's magnetic field has two poles, like a bar magnet. The poles flip at the peak of the solar activity cycle, every 11 years.

## In a star if helium fuses to make carbon, what makes the elements in between?

Phillip E.
Featured 9 months ago

The elements Lithium, Beryllium and Boron are made by cosmic rays.

#### Explanation:

The elements Hydrogen and Helium were made during the Big Bang. Helium is also made by fusion reactions in stars.

The elements Lithium Beryllium and Boron can't be made in any quantity is stars as they are intermediate steps in other fusion reactions. Any of these elements present at the birth of a star will get consumed by later reactions.

These intermediate elements (Lithium, Beryllium and Boron) are produced by cosmic rays. These are high energy protons and other particles. These collide with nuclei of Carbon and Oxygen which breaks them down and produces Lithium, Beryllium and Boron.

Carbon is produced by reactions such as the triple Helium reaction. This reaction explains what happens to Beryllium.

${\text{_2^4He+""_2^4He rarr }}_{4}^{8} B e$
${\text{_4^8Be+""_2^4He rarr }}_{6}^{12} C$

The diagram shows where all of the elements are created.

## What is granulation on the surface of the Sun caused by?

Hunaid L. Hanfee
Featured 9 months ago

Granulation is due to the convection operating below the photosphere.

#### Explanation:

The grainy appearance of the solar photosphere is produced by the tops of these convective cells and is called granulation.

Convection is the technical term for heat transport by overturning fluid or gas. We can observe convection in daily life: boiling is an example of transporting energy by convection.

This convection produces columns of rising gas just below the photosphere that are about 700 to 1000 km in diameter.

In these columns hot fluid rises up from the interior in the bright areas, spreads out across the surface, cools and then sinks inward along the dark lanes.

A typical granule lasts about 8 to 20 minutes. At one time, the sun's surface is covered by approx 3.5-4 million granules.

The granulation pattern is continually evolving as old granules are pushed aside by newly emerging ones. See this GIF for more accurate understanding of this statement:

## What are earth's four physical systems?

Hunaid L. Hanfee
Featured 8 months ago

Earth's four physical systems are $:$
$1$. Atmosphere (Air)
$2$. Lithosphere (Land)
$3$. Hydrosphere (Water)
$4$. Biosphere (Life)

#### Explanation:

Earth's each four physical systems are very important. I will describe you each one below:

$1.$ Atmosphere $\implies$ Our Earth is surrounded by gases that part of earth is said to be atmosphere. Atmosphere is extends up to approximately 10,000 km above Earth's surface. The atmosphere of our Earth is made up of three primary gases. These gases are oxygen (21%), nitrogen (78%), and argon (1%). This is very important for us because as you know we are living because of oxygen.

Atmosphere is also divided into some layers $:$

$2.$ Lithosphere $\implies$The lithosphere or geosphere is the outer, rigid shell of the solid which describes all of the land, minerals and ground that are found on and in Earth. Earth's lithosphere includes the crust and the uppermost mantle.
Basically, if it looks like solid ground, it's part of the lithosphere. This is also very important because
minerals are found in it.*

$3.$ Hydrosphere $\implies$ As you know that 'hydro' means 'water'. Hydrosphere includes all of the water on earth, from the oceans to glaciers and underground water. Most water (97%) resides in the oceans.

The hydrosphere plays a very important role in the evolution of life, as well as in weather and erosion. This is also important because we can't live without water.

$4.$ Biosphere $\implies$ The biosphere is the part of the planet where living things can be found. This includes all of the plants, animals, bacteria, fungi and single-celled organisms found on Earth.

Chemical composition:

## The radius of the sun is 0.7 million km. What percentage of the radius is taken up by the chromosphere?

Hunaid L. Hanfee
Featured 7 months ago

#0.28%#

#### Explanation:

The layer chromosphere is $2000$ km thick.

The radius of the sun is $0.7 \cdot {10}^{6}$ km.

To calculate this you have to just do same as we do in calculation of our exam's marks percentage.

Just imagine,

Your exam is of total marks of $0.7 \cdot {10}^{6}$(not possible but you have $\textcolor{w h i t e}{0000000000000000000000000000000}$to just imagine this )
out of this you got $2000$ marks.

To calculate the percentage you have to do something like this:

$= \frac{2000}{0.7 \cdot {10}^{6}} \cdot 100$

Right?

Just do same calculation for this question,
Total radius of sun is $0.7 \cdot {10}^{6}$ km.
out of this $2000$ km is chromosphere.

$= \frac{2000}{0.7 \cdot {10}^{6}} \cdot 100$

$= 0.002857 \cdot 100$

#=0.28%#

I have added image for your help by which you can know where is chromosphere of the sun.

## Mars has an average surface temperature of about 200K. Pluto has an average surface temperature of about 40K. Which planet emits more energy per square meter of surface area per second? By a factor of how much?

JMicheli
Featured 7 months ago

Mars emits $625$ times more energy per unit of surface area than Pluto does.

#### Explanation:

It is obvious that a hotter object will emit more black body radiation. Thus, we already know that Mars will emit more energy than Pluto. The only question is by how much.

This problem requires evaluating the energy of the black body radiation emitted by both planets. This energy is described as a function of temperature and the frequency being emitted:

$E \left(\nu , T\right) = \frac{2 {\pi}^{2} \nu}{c} \frac{h \nu}{{e}^{\frac{h \nu}{k T}} - 1}$

Integrating over frequency gives the total power per unit area as a function of temperature:
${\int}_{0}^{\infty} E \left(\nu , T\right) = \frac{{\pi}^{2} c {\left(k T\right)}^{4}}{60 {\left(\overline{h} c\right)}^{3}}$

(note that the above equation uses $\overline{h}$, the reduced Planck's constant, rather than $h$. It is difficult to read in Socratic's notation)

Solving for the ratio between the two, then, the result is incredibly simple. If ${T}_{p}$ is Pluto's temperature and ${T}_{m}$ is Mars' temperature then the factor $a$ can be calculated with:

$\frac{{\pi}^{2} c {\left(k {T}_{m}\right)}^{4}}{60 {\left(\overline{h} c\right)}^{3}} = a \frac{{\pi}^{2} c {\left(k {T}_{p}\right)}^{4}}{60 {\left(\overline{h} c\right)}^{3}}$
$\frac{\cancel{{\pi}^{2} c {k}^{4}}}{\cancel{60 {\left(\overline{h} c\right)}^{3}}} {T}_{m}^{4} = a \frac{\cancel{{\pi}^{2} c {k}^{4}}}{\cancel{60 {\left(\overline{h} c\right)}^{3}}} {T}_{p}^{4}$
${\left({T}_{m} / {T}_{p}\right)}^{4} = a = {\left(\frac{200}{40}\right)}^{4} = {5}^{4} = 625$ times as much

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