Term
| You used the plasma ball and fluorescent tube to demonstrate that light can be produced from the fluorescent tube without actually being plugged in. How can this occur? |
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Definition
| Plasma consists of ions and electrons and these charged particles are energized by the plasma ball electrodes and generate radio waves that can accelerate electrons in fluorescent tube to light it up. |
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Term
| Where did the most intense radiation come from on the plasma ball? |
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Definition
From the electrodes.
As the electrons move into the positively charged electrode they have the most energy and this is the source of the most intense radio waves. |
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Term
Which items, when placed between the plasma ball and the fluorescent tube could stop the tube from lighting up?
a. solid metal plate
b. metal plate with holes in it
c. cardboard
d. wood |
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Definition
| solid metal plate, metal plate with holes in it. |
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Term
The fact that radio waves CANNOT travel through metal with holes in it means that the radiation is ___________ - like.
a. a wave with a wavelength smaller than the hole
b. particle
c. a wave with a wavelength bigger than the hole |
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Definition
a wave with a wavelength bigger than the hole.
Bigger things can't get through little holes. |
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Term
Alpha radiation is actually....
a. An electron
b. Electromagnetic Radiation
c. A proton
d. A helium nucleus |
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Definition
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Term
Beta radiation is actually...
a. A part of the electromagnetic spectrum
b. An electron
c. A Proton
d. A Helium nucleus |
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Definition
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Term
Gamma radiation is actually...
a. A Part of the Electromagnetic Spectrum
b. A Proton
c. A Helium Nucleus
d. An Electron |
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Definition
| A Part of the Electromagnetic Spectrum |
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Term
| Rank the three forms of radiation (alpha, beta, and gamma) from most penetrating to least penetrating? |
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Definition
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Term
| How did the measurements of counts decrease as the geiger counter was moved further away from the gamma source? |
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Definition
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Term
| How did the measurements of counts decrease as the geiger counter was moved further away from the beta source? |
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Definition
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Term
| Why do the counts from the beta (and alpha) sources decrease differently from the gamma source? |
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Definition
| Alpha and beta can collide with air molecules and be absorbed |
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Term
| How much material was required to stop gamma radiation? |
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Definition
| More than 0.5 inches of lead |
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Term
| How much material was required to stop beta radiation? |
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Definition
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Term
They are large subatomic fragments consisting of 2 protons and 2 neutrons.
a. Gamma
b. Alpha
c. Beta |
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Definition
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Term
They are high-energy electrons ejected from the nucleus of an atom when a neutron becomes a proton.
a. Beta
b. Alpha
c. Gamma |
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Definition
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Term
They are packets of energy (photons) released from the nucleus of unstable atoms.
a. Beta
b. Gamma
c. Alpha |
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Definition
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Term
They are negatively charged.
a. Alpha
b. Beta
c. Gamma |
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Definition
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Term
In lecture, you learned about how the P-P chain generates energy in the Sun's core. Can you identify the various steps involved?
a. 3He + 3He ->4He + 2p
b. e+ + D + neutrino -> p + p
c. p + p -> e+ + D + neutrino , e+ + e- -> gamma ray
d. 3He + p ->4He
e. D + p ->3He + gamma ray |
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Definition
| p + p -> e+ + D + neutrino , e+ + e- -> gamma ray |
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Term
What is the second step of the proton chain?
a. p + p -> e+ + D + neutrino , e+ + e- -> gamma ray
b. 3He + 3He ->4He + 2p
c. e+ + D + neutrino-> p + p
d. 3He + p ->4He
e. D + p ->3He + gamma ray |
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Definition
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Term
What is the third step of the proton chain?
a. D + p ->3He + gamma ray
b. D + p ->4He + neutrino
c. p + p -> e+ + D + neutrino + e- -> gamma ray
d. 3He + 3He ->4He + 2p
e. 3He + p ->4He |
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Definition
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Term
Which are of the following are true regarding the theory that the Sun's power is generated by its own collapse?
Select one or more:
a. This process could power the sun for 22 million years.
b. This process could power the sun for 4.5 billion years.
c. This theory holds today.
d. This theory is outdated and no longer accepted.
e. This process requires the Sun's radius to shrink by 50 m per year. |
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Definition
This process could power the sun for 22 million years.
This theory is outdated and no longer accepted.
This theory is outdated and no longer accepted. |
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Term
Why is the surface of Venus so hot compared to all the other planets? (check all that apply)
a. It is the closest to the Sun.
b. High winds.
c. Current volcanic activity.
d. Solar radiation is trapped by CO2 in the atmosphere (the greenhouse effect).
e. Solar radiation is trapped by N2 in the atmosphere (the greenhouse effect). |
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Definition
| Solar radiation is trapped by CO2 in the atmosphere (the greenhouse effect). |
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Term
What happens when an atom absorbs a photon of light that has energy greater than its atomic binding energy?
a. Neutron becomes unbound from the atom
b. Electron becomes unbound from the atom
c. Proton falls to a lower energy level
d. Proton becomes unbound from the atom
e. Electron falls to a lower energy level |
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Definition
| Electron becomes unbound from the atom |
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Term
Which of the following statements are TRUE concerning the Bohr model of the atom?
a. Most of the atom is empty space other than a dense negatively charged nucleus.
b. Energy states are quantized or discrete. Correct
c. Most of the atom is empty space other than a dense positively charged nucleus.
d. The energy state closest to the nucleus has the largest energy.
e. Energy states are continuous. |
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Definition
Energy states are quantized or discrete
Most of the atom is empty space other than a dense positively charged nucleus. |
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Term
| You recorded the orientation of the magnetic field from the bar magnets when it was slipped into the cube of iron filings. What happens to the iron filings? |
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Definition
| They lined up to form loop-like structures |
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Term
| A wire was placed within a magnetic field caused by two permanent magnets. Describe what happened when a current was run through the wire. |
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Definition
| The wire was deflected out of the magnetic field and away from both magnets. |
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Term
| When the current in the wire was reversed, how did it behave differently? |
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Definition
| The wire was deflected out of the magnetic field in the opposite direction to before. |
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Term
| Describe what happened when the solid aluminum plate was swung between the two magnets. |
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Definition
| The plate slowed down to nothing after the first swing. |
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Term
| Describe what happened when the "rake" aluminum plate was swung between the two magnets. |
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Definition
| Nothing, it kept swinging. |
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Term
The ring launcher worked as follows:
a. A coil of wire is present at the bottom of the system and current is rapidly switched on to generate a magnet field.
b. The ring launcher works equally well for rings with slits through them versus a solid ring.
c. A permanent magnet is present at the bottom of the system.
d. The presence of a rapidly varying magnetic field induces a current in the cylinder to generate a repelling magnetic field which then launches the ring. |
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Definition
A coil of wire is present at the bottom of the system and current is rapidly switched on to generate a magnet field.
The presence of a rapidly varying magnetic field induces a current in the cylinder to generate a repelling magnetic field which then launches the ring. |
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Term
Your lab experiments showed that γ-rays (γ is the greek letter gamma) are stopped by a dense material such as lead. The Sun's inner core is on average 10 times denser than lead (though not composed of lead) and the absorbed gamma rays are re-emitted. (Note that the Sun's diameter is 1.4 x 10^6 km).
If a γ-ray is stopped by 2 cm of lead in the laboratory, then about how far will it travel in the Sun's interior before it gets absorbed?
a. 0.02 cm
b. 20 cm
c. 0.2 cm
d. 2 x 10^10 cm
e. 2 cm |
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Definition
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Term
Your lab experiments showed that γ-rays (γ is the greek letter gamma) are stopped by a dense material such as lead. The Sun's inner core is on average 10 times denser than lead (though not composed of lead) and the absorbed gamma rays are re-emitted. (Note that the Sun's diameter is 1.4 x 10^6 km).
The Sun's inner core extends from the center out to about 25% of its full radius. About how many times will a γ-ray be absorbed and re-emitted before it reaches the edge of the core if it travels in a straight line?
a. 9 x 10^5
b. 9 x 10^10
c. 4.5 x 10^5
d. 4.5 x 10^10
e. 9000 |
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Definition
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Term
If the speed of light is 3x10^5 km/sec and a γ-ray takes 10^5 years to exit the core of the Sun: how many times faster is the speed of light compared to the average outward velocity of a γ-ray?
a. 2 x 10^8
b. 5.5 x 10^12
c. 5.5
d. 1 x 10^13
e. 5.5 x 10^7 |
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Definition
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Term
What is the primary reason why the γ-ray takes as long as it does to reach the edge of the Sun's core?
a. The speed of light is much slower inside the core of a star.
b. γ-rays don't follow a straight line in the core, but instead follow a 'random walk' path that takes much more time
c. Convection in the core transfers energy back to the center faster than it can escape by radiation.
d. There is a 'hold time' between absorption and re-emission of a γ-ray that makes the speed appear to be slow.
e. γ-rays are radioactive particles that naturally travel slower than light. |
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Definition
| γ-rays don't follow a straight line in the core, but instead follow a 'random walk' path that takes much more time |
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Term
Which of the following things about neutrinos are true?
a. Neutrinos are tiny, nearly massless, neutral elementary particles that interact with matter only rarely.
b. The Homestake Neutrino Experiment detects neutrinos when an atom of Uranium changes into Plutonium, which then decays to produce a beta particle.
c. Neutrinos escape the Sun's core without being scattered.
d. We observe far too many neutrinos in the Sun, which is a quandary we call the "Solar neutrino problem".
e. Solar Neutrinos energies are directly related to different fusion reactions in the Sun's core. |
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Definition
Neutrinos are tiny, nearly massless, neutral elementary particles that interact with matter only rarely.
Neutrinos escape the Sun's core without being scattered.
Solar Neutrinos energies are directly related to different fusion reactions in the Sun's core. |
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Term
Which of the following are false statements about Neutrinos?
Select one or more:
a. Neutrinos interact with a human body about once every 70 seconds
b. Neutrinos are free electrons that are produced in certain nuclear reactions.
c. Neutrinos interact with a human body about once every 70 years.
d. We know neutrinos come from the Sun because they are only detectable during the day time.
e. Neutrino characteristics are specific to different types of sub-atomic particles, but will oscillate between these states. |
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Definition
Neutrinos interact with a human body about once every 70 seconds
Neutrinos are free electrons that are produced in certain nuclear reactions.
We know neutrinos come from the Sun because they are only detectable during the day time. |
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Term
| The Solar Neutrino Problem is... |
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Definition
| That we detect far fewer neutrinos than we expect from the Sun's core. |
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Term
| Granules on the Sun are about the size of... |
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Definition
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Term
Which of the following are studied using Magnetograms?
Select all that apply:
a. Prominent loops connecting active regions
b. Granule convection
c. Sunspot structure
d. Solar differential rotation
e. Solar Filaments |
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Definition
Prominent loops connecting active regions.
Sunspot structure.
Solar Filaments. |
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Term
The Solar Cycle refers to (indicate all that apply):
Select one or more:
a. The period over which the Sun's super convection cells oscillate.
b. The period over which the number of sunspots increases and decreases.
c. The changing pattern of heating at the surface of the Earth, which gives rise to seasons.
d. The period over which the Sun's magnetic field flips from N-S to S-N
e. The period over which the solar wind activity at the Earth increases and decreases. |
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Definition
The period over which the number of sunspots increases and decreases.
The period over which the Sun's magnetic field flips from N-S to S-N.
The period over which the solar wind activity at the Earth increases and decreases. |
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Term
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Definition
| The large-scale radial outflow structures that dominate the corona |
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Term
Which of the following descriptions apply to the Chromosphere?
Select one or more:
a. The hot (~2 million degrees) upper atmosphere of the sun.
b. A region where the temperature is 6,000 to 20,000 K
c. The thin layer above the photosphere that contains long, thin structures of luminous gas called "Spicules".
d. The coldest regions of the sun from which visible light is emitted.
e. The region defining the influence of the Sun through the solar wind, ending with the interstellar medium.
f. A 6000K bright region of the atmosphere characterized by convective 'granules'. |
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Definition
A region where the temperature is 6,000 to 20,000 K.
The thin layer above the photosphere that contains long, thin structures of luminous gas called "Spicules". |
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Term
Which of the following descriptions best apply to the corona?
Select one or more:
a. The outermost luminous region of the sun that remains visible during a solar eclipse.
b. The thin layer above the photosphere that contains long, thin structures of luminous gas called Spicules.
c. The hot (~1-2 million degrees) upper atmosphere of the sun.
d. The thinnest (300 km) region of the solar atmosphere from which most visible light is emitted.
e. An ionized region of the solar atmosphere that produces only individual plasma emission lines.
f. The coldest regions of the sun from which visible light is emitted. |
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Definition
The outermost luminous region of the sun that remains visible during a solar eclipse.
The hot (~1-2 million degrees) upper atmosphere of the sun.
An ionized region of the solar atmosphere that produces only individual plasma emission lines. |
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Term
Which of the following descriptions apply to the heliosphere?
Select one or more:
a. The higher temperature convective region of the sun from which visible light is emitted.
b. The region of the solar atmosphere that interacts directly with the interstellar medium.
c. The region defining the influence of the Sun through the solar wind.
d. The outermost luminous region of the sun that remains visible during a solar eclipse.
e. The thin layer of the solar atmosphere that contains long, thin structures of luminous gas called 'Spicules'.
f. The coldest region of the sun, from which visible light is emitted.
g. The part of the solar atmosphere responsible for space weather events caused by "Halo CMEs".
h. The hot (~2 million degrees) upper atmosphere of the sun. |
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Definition
The region of the solar atmosphere that interacts directly with the interstellar medium.
The region defining the influence of the Sun through the solar wind. |
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Term
Which of these descriptions applies to the Photosphere?
Select one or more:
a. The coldest region of the sun, from which visible light is emitted.
b. The hot (~2 million degrees K) upper atmosphere of the sun.
c. The region defining the influence of the Sun through the solar wind, ending with the interstellar medium.
d. A hot 20000K region heated by sound waves that is bright in H-alpha emission and characterized by Spicules.
e. The thinnest (300 km) layer of the solar atmosphere.
f. The outermost luminous region of the sun that remains visible during a solar eclipse. |
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Definition
The coldest region of the sun, from which visible light is emitted.
The thinnest (300 km) layer of the solar atmosphere. |
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Term
What is the approximate radial extent of the Heliosphere?
a. 100-200 AU
b. The solar atmosphere only
c. 100-200 million km
d. 1,000-2,000 AU
e. 10-20 AU |
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Definition
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Term
Which of these solar events is commonly associated with the emission of X-rays?
a. Solar Flares
b. Coronal Holes
c. Coronal Mass Ejections |
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Definition
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Term
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Definition
the process of obtaining energy by BREAKING THINGS APART.
Occurs during radioactive decay.
Is naturally occurring and happens in power plants. |
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Term
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Definition
the process of obtaining energy by ADDING THINGS TOGETHER.
the combining of two nuclei to form a heavier nucleus.
Occurs inside the core of the Sun.
Is the magic bullet for solving human energy problems. |
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Term
| Magnetic Confinement for fusion |
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Definition
Uses magnetic fields to confine hot plasmas.
• Types of expt:
Tokamaks (ITER, NSTX,
Alcator...)
Stellerators
Compact Torus (HIT-‐SI...)
Innovative Confinement Concepts |
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Term
| Inertial Confinement for fusion |
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Definition
Uses lasers to crush a full target very rapidly.
• Types of facilities:
Solid State Lasers(NIF,
NRL...)
Gas Laser (NRL, PALS...) |
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Term
| Eddington's final theory? |
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Definition
1) Gravitational forces pressurize the center of the Sun.
2) Compression heats the interior (he thought to 40 million K).
3) Thermal collisions strip electrons from their nucleus, creating a
plasma.
4) Free protons collide and stick to form helium nuclei.
5) The mass difference between H and He is converted to energy and released as light! |
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Term
| What is the different between spontaneous fission and stimulated fission? |
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Definition
A spontaneous fission can decay into one or more different (lighter) elements, releasing energy as it decays.
Stimulated Fission occurs when the interaction with another particle triggers element breakup. |
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Term
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Definition
| a type of radioactive decay in which an electron or a positron is emitted from an atom. |
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Term
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Definition
| A neutral subatomic particle with a mass close to zero and half-integral spin, rarely reacting with normal matter. |
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