Question 1

If a coronal mass ejection occurs on the Sun that expels material at a speed of 800 km/s,how long will it take these charged particles to reach the Earth?

Accepted Answer

A) 0.7 day 
B) 1.4 days 
C) 1.8 days 
D) 2.2 days 
E) 3.5 days 
A) 0.7 day 
B) 1.4 days 
C) 1.8 days 
D) 2.2 days 
E) 3.5 days D

Question 2

The Sun exhibits differential rotation.Explain what differential rotation is.Which planets also do this? Why don't the others?

Accepted Answer

Differential rotation means that the equator of an object rotates more rapidly than the higher latitude regions.In addition to the Sun,the giant planets all do this.The terrestrial planets can't have differential rotation because they all have solid surfaces that must rotate together.

Question 3

The picture below shows a diagram of the Sun with zones labeled A,B,and C.  
Explain how energy is being transferred in each of the three regions.

Accepted Answer

Region A is the radiative zone,where energy is being carried by photons.Region B is the convective zone,where moving gas carries the energy.Region C is outside the Sun,where the energy is again being carried by photons.

Question 4

The magnetic field of the Sun is continuously produced and deformed by:

Accepted Answer

A) its differential rotation 
B) the solar wind 
C) changes in the rate of nuclear fusion in the core 
D) a liquid conducting layer in the interior 
E) This is a trick question.The solar magnetic field is primordial. 
A) its differential rotation 
B) the solar wind 
C) changes in the rate of nuclear fusion in the core 
D) a liquid conducting layer in the interior 
E) This is a trick question.The solar magnetic field is primordial.

Question 5

In the radiative zone inside the Sun,photons are transported from the core to the convective zone in a matter of seconds.

Accepted Answer

A) True 
 B)False

Question 6

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

Accepted Answer

A) The altitudes of orbiting satellites decrease. 
B) Airplanes have trouble navigating. 
C) Stronger auroras are seen. 
D) Power grids can be damaged. 
E) All of the above can be caused by increased solar activity. 
A) The altitudes of orbiting satellites decrease. 
B) Airplanes have trouble navigating. 
C) Stronger auroras are seen. 
D) Power grids can be damaged. 
E) All of the above can be caused by increased solar activity.

Question 7

The best wavelength to use to observe a solar prominence is:

Accepted Answer

A) 550 nm,green visible light 
B) 656 nm,a red hydrogen emission line 
C) 16 mm,an ultraviolet emission line 
D) 21 cm,microwave emission 
E) 0.02 nm,X-ray emission 
A) 550 nm,green visible light 
B) 656 nm,a red hydrogen emission line 
C) 16 mm,an ultraviolet emission line 
D) 21 cm,microwave emission 
E) 0.02 nm,X-ray emission

Question 8

Solar wind particles hit the surface of the Moon,but they don't make it to the surface of the Earth because the Earth:

Accepted Answer

A) is larger than the Moon 
B) is warmer than the Moon 
C) has an atmosphere while the Moon does not 
D) has a magnetic field while the Moon does not 
E) is further from the Sun than the Moon 
A) is larger than the Moon 
B) is warmer than the Moon 
C) has an atmosphere while the Moon does not 
D) has a magnetic field while the Moon does not 
E) is further from the Sun than the Moon

Question 9

What do astronomers mean when they say that the Sun makes energy by hydrogen burning?

Accepted Answer

A) The Sun is combusting hydrogen in a fire and releasing energy. 
B) The Sun is fusing hydrogen into uranium and releasing energy. 
C) The Sun is made of mostly hydrogen at very high temperature. 
D) The Sun is fusing hydrogen into helium and releasing energy. 
E) The Sun is accumulating hydrogen from the solar wind and releasing energy. 
A) The Sun is combusting hydrogen in a fire and releasing energy. 
B) The Sun is fusing hydrogen into uranium and releasing energy. 
C) The Sun is made of mostly hydrogen at very high temperature. 
D) The Sun is fusing hydrogen into helium and releasing energy. 
E) The Sun is accumulating hydrogen from the solar wind and releasing energy.

Question 10

What keeps the gas in the Sun's corona from flying away from the Sun?

Accepted Answer

A) gravity 
B) strong nuclear force 
C) the Sun's magnetic field 
D) the solar wind 
E) sunspots 
A) gravity 
B) strong nuclear force 
C) the Sun's magnetic field 
D) the solar wind 
E) sunspots

Question 11

When you turn on the heater in a car,the passengers in the front seat warm up first,then eventually the warm air gets to the passengers in the back seat.This is an example of energy being transported by:

Accepted Answer

A) radiation 
B) convection 
C) conduction 
D) convection and conduction 
E) radiation and conduction 
A) radiation 
B) convection 
C) conduction 
D) convection and conduction 
E) radiation and conduction

Question 12

The interior zones of the Sun are distinguished by:

Accepted Answer

A) jumps in density between zones 
B) their temperature profiles 
C) pressure differences inside each zone 
D) their modes of energy transport 
E) all of the above 
A) jumps in density between zones 
B) their temperature profiles 
C) pressure differences inside each zone 
D) their modes of energy transport 
E) all of the above

Question 13

Through hydrogen fusion,the Sun loses approximately 4 million tons of mass each second.If it burns hydrogen at this rate for 10 billion years,what percentage of its original mass will it lose in all? (Note: The mass of the Sun is 1.99 × 1030 kg,and 1 ton = 1,000 kg. )

Accepted Answer

The total amount of mass lost is: 4000 ×

Question 14

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 15

The Sun's internal magnetic field becomes tangled up over time because of:

Accepted Answer

A) coronal holes 
B) coronal mass ejections 
C) differential rotation 
D) temperature changes in the Sun's core 
E) all of the above 
A) coronal holes 
B) coronal mass ejections 
C) differential rotation 
D) temperature changes in the Sun's core 
E) all of the above

Question 16

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 17

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 18

The majority of the Sun's energy comes from:

Accepted Answer

A) gravitational contraction 
B) nuclear fission of uranium 
C) hydrogen fusion 
D) helium burning 
E) burning material as in a fire 
A) gravitational contraction 
B) nuclear fission of uranium 
C) hydrogen fusion 
D) helium burning 
E) burning material as in a fire

Question 19

The solar neutrino problem was solved by:

Accepted Answer

A) adjusting the rate of hydrogen burning in solar models 
B) improving detector efficiencies so more neutrinos were observed 
C) postulating that neutrinos had mass and oscillated between three different types 
D) lowering the percentage of helium in models of solar composition 
E) correctly measuring the density of the Sun's interior 
A) adjusting the rate of hydrogen burning in solar models 
B) improving detector efficiencies so more neutrinos were observed 
C) postulating that neutrinos had mass and oscillated between three different types 
D) lowering the percentage of helium in models of solar composition 
E) correctly measuring the density of the Sun's interior

Question 20

If a sunspot appears one-quarter as bright as the surrounding photosphere,and the average temperature of the photosphere is 5800 K,what is the temperature of the gas in this sunspot?

Accepted Answer

A) 3625 K 
B) 4100 K 
C) 4500 K 
D) 5200 K 
E) 5500 K 
A) 3625 K 
B) 4100 K 
C) 4500 K 
D) 5200 K 
E) 5500 K

Exam 14: Our Starthe Sun

If a coronal mass ejection occurs on the Sun that expels material at a speed of 800 km/s,how long will it take these charged particles to reach the Earth?

The Sun exhibits differential rotation.Explain what differential rotation is.Which planets also do this? Why don't the others?

The picture below shows a diagram of the Sun with zones labeled A,B,and C. Explain how energy is being transferred in each of the three regions.

The magnetic field of the Sun is continuously produced and deformed by:

In the radiative zone inside the Sun,photons are transported from the core to the convective zone in a matter of seconds.

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

The best wavelength to use to observe a solar prominence is:

Solar wind particles hit the surface of the Moon,but they don't make it to the surface of the Earth because the Earth:

What do astronomers mean when they say that the Sun makes energy by hydrogen burning?

What keeps the gas in the Sun's corona from flying away from the Sun?

When you turn on the heater in a car,the passengers in the front seat warm up first,then eventually the warm air gets to the passengers in the back seat.This is an example of energy being transported by:

The interior zones of the Sun are distinguished by:

Through hydrogen fusion,the Sun loses approximately 4 million tons of mass each second.If it burns hydrogen at this rate for 10 billion years,what percentage of its original mass will it lose in all? (Note: The mass of the Sun is 1.99 × 1030 kg,and 1 ton = 1,000 kg. )

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.

The Sun's internal magnetic field becomes tangled up over time because of:

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

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

The majority of the Sun's energy comes from:

The solar neutrino problem was solved by:

If a sunspot appears one-quarter as bright as the surrounding photosphere,and the average temperature of the photosphere is 5800 K,what is the temperature of the gas in this sunspot?

Why Learn Astronomy

Patterns in the Skymotions of Earth

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Birth and Evolution of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquid the Giant Planets

Planetary Adornments Moons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Star Formation and the Interstellar Medium

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Relativity and Black Holes

The Expanding Universe

Galaxies

The Milky Waya Normal Spiral Galaxy

Modern Cosmology

Large-Scale Structure in the Universe

Life

Filters

Through hydrogen fusion,the Sun loses approximately 4 million tons of mass each second.If it burns hydrogen at this rate for 10 billion years,what percentage of its original mass will it lose in all? (Note: The mass of the Sun is 1.99 × 10³⁰ kg,and 1 ton = 1,000 kg. )

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.