Question 1

What is "limb darkening"? Explain why limb darkening occurs in the Sun.

Accepted Answer

Limb darkening means that the edges of t

Question 2

How do periods of strong solar activity affect near-Earth orbiting spacecraft?

Accepted Answer

At solar maxima,the amount of extreme ul

Question 3

The fact that the surface of the Sun rings like a bell lets us understand its interior better.

Accepted Answer

A) True 
 B)False

Question 4

The energy that fuels the Sun is generated:

Accepted Answer

A)  only on its surface 
B)  only in its core 
C)  both in its core and on its surface 
D)  in its core,on the surface,and in the solar wind 
A)  only on its surface 
B)  only in its core 
C)  both in its core and on its surface 
D)  in its core,on the surface,and in the solar wind

Question 5

In the proton-proton chain,the net reaction is that 4 hydrogen nuclei are converted to 1 helium nucleus and __________ are released.

Accepted Answer

A)  visible wavelength photons 
B)  gamma ray photons,positrons,and neutrinos 
C)  ultraviolet photons and neutrinos 
D)  X-ray photons,electrons,and neutrinos 
A)  visible wavelength photons 
B)  gamma ray photons,positrons,and neutrinos 
C)  ultraviolet photons and neutrinos 
D)  X-ray photons,electrons,and neutrinos

Question 6

If coronal holes covered a larger fraction of the Sun's surface,the solar wind would contain a higher density of particles.

Accepted Answer

A) True 
 B)False

Question 7

Show that a star with the same mass,composition,radius,and luminosity as the Sun,but with a higher temperature (that is,a "too-hot" Sun),leads to a contradiction.

Accepted Answer

If the temperature is higher,more energy

Question 8

Why is hydrogen burning the main energy source for main-sequence stars? Give at least two reasons.

Accepted Answer

(1)Hydrogen is the most abundant element

Question 9

In the proton-proton chain,the net reaction is that 4 protons are converted into 1 helium nucleus.What other by-products are released in this reaction,and why?

Accepted Answer

Energy is released in the form of gamma

Question 10

If neutrinos oscillated between five different types of neutrino during their transit from the Sun to Earth,then how many neutrinos would we have detected compared to what was emitted by the Sun?

Accepted Answer

A)  One-third as many 
B)  One-fourth as many 
C)  One-fifth as many 
D)  We would detect no neutrinos 
A)  One-third as many 
B)  One-fourth as many 
C)  One-fifth as many 
D)  We would detect no neutrinos

Question 11

Which of the following are manifestations of solar magnetic activity?

Accepted Answer

A)  Sunspots 
B)  Prominences 
C)  Flares 
D)  All of the above 
A)  Sunspots 
B)  Prominences 
C)  Flares 
D)  All of the above

Question 12

In the figure below,label the regions of the Sun.

Accepted Answer

The inner region is the core,t

Question 13

Nuclei of atoms are held together by gravity.

Accepted Answer

A) True 
 B)False

Question 14

Which of the following is NOT a result of an increase in solar activity?

Accepted Answer

A)  The height of orbiting satellites decreases. 
B)  Airplanes have trouble navigating. 
C)  Stronger auroras are seen. 
D)  All of the above can be caused by increased solar activity. 
A)  The height of orbiting satellites decreases. 
B)  Airplanes have trouble navigating. 
C)  Stronger auroras are seen. 
D)  All of the above can be caused by increased solar activity.

Question 15

Which of the following layers of the Sun makes up the majority of its interior?

Accepted Answer

A)  The core 
B)  The radiative zone 
C)  The convective zone 
D)  The photosphere 
A)  The core 
B)  The radiative zone 
C)  The convective zone 
D)  The photosphere

Question 16

If a sunspot appears one-quarter as bright as the surrounding photosphere,and the average temperature of the photosphere is 5,800 K,what is the temperature of the gas in this sunspot?

Accepted Answer

A)  4100 K 
B)  4500 K 
C)  5200 K 
D)  5500 K 
A)  4100 K 
B)  4500 K 
C)  5200 K 
D)  5500 K

Question 17

Density,temperature,and pressure increase as you move inward in the interior of the Sun.This means that the force of gravity,(Fg = GMm/r2),__________ as you move inward toward the core.

Accepted Answer

A)  increases 
B)  decreases 
C)  stays the same 
D)  There is not enough information to answer. 
A)  increases 
B)  decreases 
C)  stays the same 
D)  There is not enough information to answer.

Question 18

Calculate the amount of energy released by converting 4 hydrogen atoms into 1 helium atom.The mass of a hydrogen atom is 1.67 × 10-24 kg; the mass of a helium atom is 6.65 × 10-24 g.The speed of light is 3 × 108 m/s.

Accepted Answer

First,we need to calculate the amount of

Question 19

Examine the figure below.Explain why it takes so long for gamma-ray energy to find its way to the outer layers of the Sun.

Accepted Answer

Gamma-ray radiation travels only short p

Question 20

In the proton-proton chain,the net result is that 4 protons are converted into 1 helium nucleus and energy,electrons,and neutrinos are released.

Accepted Answer

A) True 
 B)False

What is "limb darkening"? Explain why limb darkening occurs in the Sun.

How do periods of strong solar activity affect near-Earth orbiting spacecraft?

The fact that the surface of the Sun rings like a bell lets us understand its interior better.

The energy that fuels the Sun is generated:

In the proton-proton chain,the net reaction is that 4 hydrogen nuclei are converted to 1 helium nucleus and __________ are released.

If coronal holes covered a larger fraction of the Sun's surface,the solar wind would contain a higher density of particles.

Show that a star with the same mass,composition,radius,and luminosity as the Sun,but with a higher temperature (that is,a "too-hot" Sun),leads to a contradiction.

Why is hydrogen burning the main energy source for main-sequence stars? Give at least two reasons.

In the proton-proton chain,the net reaction is that 4 protons are converted into 1 helium nucleus.What other by-products are released in this reaction,and why?

If neutrinos oscillated between five different types of neutrino during their transit from the Sun to Earth,then how many neutrinos would we have detected compared to what was emitted by the Sun?

Which of the following are manifestations of solar magnetic activity?

In the figure below,label the regions of the Sun.

Nuclei of atoms are held together by gravity.

Which of the following is NOT a result of an increase in solar activity?

Which of the following layers of the Sun makes up the majority of its interior?

If a sunspot appears one-quarter as bright as the surrounding photosphere,and the average temperature of the photosphere is 5,800 K,what is the temperature of the gas in this sunspot?

Density,temperature,and pressure increase as you move inward in the interior of the Sun.This means that the force of gravity,(F_g = GMm/r²),__________ as you move inward toward the core.

Calculate the amount of energy released by converting 4 hydrogen atoms into 1 helium atom.The mass of a hydrogen atom is 1.67 × 10^-24 kg; the mass of a helium atom is 6.65 × 10^-24 g.The speed of light is 3 × 10⁸ m/s.

Examine the figure below.Explain why it takes so long for gamma-ray energy to find its way to the outer layers of the Sun.

In the proton-proton chain,the net result is that 4 protons are converted into 1 helium nucleus and energy,electrons,and neutrinos are released.

Our Place in the Universe

Patterns in the Skymotions of Earth

Laws of Motion

Light and Telescopes

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, Earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

The Expansion of Space

The Realm of the Galaxies

Our Galaxy: The Milky Way

Modern Cosmology and the Origin of Structure

Life in the Universe

Filters

Exam 11: Our Star: The Sun

What is "limb darkening"? Explain why limb darkening occurs in the Sun.

How do periods of strong solar activity affect near-Earth orbiting spacecraft?

The fact that the surface of the Sun rings like a bell lets us understand its interior better.

The energy that fuels the Sun is generated:

In the proton-proton chain,the net reaction is that 4 hydrogen nuclei are converted to 1 helium nucleus and __________ are released.

If coronal holes covered a larger fraction of the Sun's surface,the solar wind would contain a higher density of particles.

Show that a star with the same mass,composition,radius,and luminosity as the Sun,but with a higher temperature (that is,a "too-hot" Sun),leads to a contradiction.

Why is hydrogen burning the main energy source for main-sequence stars? Give at least two reasons.

In the proton-proton chain,the net reaction is that 4 protons are converted into 1 helium nucleus.What other by-products are released in this reaction,and why?

If neutrinos oscillated between five different types of neutrino during their transit from the Sun to Earth,then how many neutrinos would we have detected compared to what was emitted by the Sun?

Which of the following are manifestations of solar magnetic activity?

In the figure below,label the regions of the Sun.

Nuclei of atoms are held together by gravity.

Which of the following is NOT a result of an increase in solar activity?

Which of the following layers of the Sun makes up the majority of its interior?

If a sunspot appears one-quarter as bright as the surrounding photosphere,and the average temperature of the photosphere is 5,800 K,what is the temperature of the gas in this sunspot?

Density,temperature,and pressure increase as you move inward in the interior of the Sun.This means that the force of gravity,(Fg = GMm/r2),__________ as you move inward toward the core.

Calculate the amount of energy released by converting 4 hydrogen atoms into 1 helium atom.The mass of a hydrogen atom is 1.67 × 10-24 kg; the mass of a helium atom is 6.65 × 10-24 g.The speed of light is 3 × 108 m/s.

Examine the figure below.Explain why it takes so long for gamma-ray energy to find its way to the outer layers of the Sun.

In the proton-proton chain,the net result is that 4 protons are converted into 1 helium nucleus and energy,electrons,and neutrinos are released.

Our Place in the Universe

Patterns in the Skymotions of Earth

Laws of Motion

Light and Telescopes

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, Earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

The Expansion of Space

The Realm of the Galaxies

Our Galaxy: The Milky Way

Modern Cosmology and the Origin of Structure

Life in the Universe

Filters

Density,temperature,and pressure increase as you move inward in the interior of the Sun.This means that the force of gravity,(F_g = GMm/r²),__________ as you move inward toward the core.

Calculate the amount of energy released by converting 4 hydrogen atoms into 1 helium atom.The mass of a hydrogen atom is 1.67 × 10^-24 kg; the mass of a helium atom is 6.65 × 10^-24 g.The speed of light is 3 × 10⁸ m/s.