GSTR 332 Final

Explain the three basic types of plate boundaries.

(1) Divergent, in which two plates are moving away from each other, (2) Convergent, in which they are pressing against each other, and (3) Transform, in which they are scraping alongside each other.

What are the four classic states of matter, and how are they defined?

1. A gas expands to fill its container. 2. A liquid maintains a constant volume, but take the shape of its container. 3. A solid maintains both its volume and its shape. 4. A plasma is an ionized gas with can be contained in a magnetic field.

What two important features of "chemistry" is it important to know?

1. Chemistry takes place in the outer ("valence") shells of atoms. 2. A significant portion of the characteristics of the resulting molecule is determined by its physical shape.

What must we be able to show in order to say that "A causes B"?

1. That A comes before B in time 2. That A correlates with B 3. That there is some mechanism by which A can "connect" to B 4. That we have discounted any possible C which actually causes them both.

List at least three facts that serve as evidence for the Big Bang.

1. Universal expansion 2. Cosmic microwave background radiation 3. Abundance of light elements 4. Lack of antimatter 5. Hubble's constant 6. The darkness of the night sky (Olber's paradox)

What are the three different ways in which heat is transferred?

1. conduction 2. convection 3. radiation

What is a star?

A large ball of plasma (or gas) that radiates energy into space through fusion reactions powered by gravity.

What is the Nebular Hypothesis, and what evidence exists for it?

About 4.5 billion years ago, a large, rotating cloud of gas coalesced under gravitational attraction to form small chunks of material called planetesimals. These collided with each other to produce larger and larger objects. Most of the mass, however, coalesced in the center to produce the Sun. Evidence for this is (1) the difference between the inner (terrestrial) planets, which are small rocky worlds and the outer (Jovian) planets, which are large balls of frozen gas, essentially the same as the original nebular medium, (2) the planets revolve around the sun in the same direction as its rotation (3) most of the planets rotate on their axes in the same direction as the sun's rotation, (4) the plane of revolution of most of the planets is within about 5° of the ecliptic. It's hard to believe that all this is just a coincidence!

What is the difference between AC and DC current? What kind is produced by a battery?

Alternating Current is produced by a conductor spinning through a magnetic field. The electrons in the conductor move through it first in one direction, then reverse -- twice for each spin cycle. Electrons in Direct Current move in one direction only, from the "negative" side of the source to the "positive" side. This is the kind produced by a battery.

Give an example of a situation in which entropy increases.

Any will do, provided that it is an example of a situation in which order has decreased. Bedrooms tend to become messier, bodies age and die, ice melts, and so on.

Explain what an isotope is, and what an ion is.

Atoms of the same element which differ in the number of neutrons they have are known as "isotopes" of that element. "Ions" are atoms which have an unequal number of protons and electrons.

According to current science, what is the likely fate of the universe?

Even counting dark matter, we estimate that only about 20% of the mass necessary to slow down the expansion of the universe exists. In fact, recent (1999) observations indicate that the expansion might actually be speeding up. We probably live in an "open" universe, which means it will expand forever, cooling as it does, eventually to absolute zero. Sometimes called "Heat Death."

What is "wave-particle duality"?

Every quantum particle (atom-sized or smaller) exhibits qualities of waves or particles, depending upon how they are observed.

List the four fundamental forces, from weakest to strongest.

Gravity, Weak Force, Electromagnetic Force, Strong Force

What is the difference between "heat" and "temperature"? Does a pint of boiling water at 100 oC contain as much heat as a quart of boiling water at 100 oC?

Heat is a form of energy that flows from a warmer object to a cooler object. It is a measure of the quantity of atomic kinetic energy contained in an object, often measured in calories. Temperature is a relative term and says how vigorously the atoms in the substance are moving. A quart of boiling water therefore has the same temperature as a pint of boiling water, but twice as much heat (because there is twice as much water).

Explain the difference between longitudinal waves and transverse waves, and give an example of each.

In T-waves, the motion of the wave itself is different from (perpendicular to) the motion of the medium in which the wave moves. For example, waves in water move across the surface of the water, while the water itself merely moves up and down. In L-waves, the wave moves in the same direction as the medium through which it moves. Sound waves, for example, are created by moving air molecules back and forth, which then collide with neighboring molecules, inducing them to continue the process.

What are the three major ways atoms bond to form molecules? Give a brief explanation of each.

In an IONIC bond, atoms that lose or gain electrons to have full valence shells will then become ions, and may stick together electrostatically. In COVALENT bonds, two or more atoms fill their valence shells by 3 sharing electrons. A special type of this is the METALLIC bond, in which the electrons are passed around and shared by all the atoms in the material.

Briefly describe the Milky Way galaxy.

It is a spiral galaxy consisting of about 100 billion stars, about 100,000 light years across, with a central bulge known as the nucleus, and bright regions (spiral arms) where new stars are being formed.

What causes the surface tension of water, and why?

It is caused by a hydrogen bond. When two H atoms covalently bond with one O, they are offset on one side at about a 135 degree angle -- making the molecule look like "Mickey Mouse" ears. The shared electrons spend more time going around the O end of the molecule, since it's so much bigger, and therefore that end takes on a net negative polarity, with the H end being positively charged. Two H2O molecules can then chain together with a weak electrostatic link.

What is a "half-life"?

It is the empirically determined length of time it takes for half of the population of something to disappear or transform.

Explain the "First Principle of Science" (according to M. Berheide!)

It may be stated as "There exists an objective reality," and means essentially that at least some of the features of reality are as they are independently of what we might believe. It deserves primacy of place because, unless science and scientists believe that, there can be no investigation into the physical world, no learning.

What is going to happen to our Sun?

It will complete its hydrogen-burning phase in a few billion years, enter into a "helium-burning" phase, turn into a Red Giant, and then into a White Dwarf. Eventually, billions more years later, it will cool into a chunk of mostly carbon.

Would it take as much energy for you to climb ten feet up a ladder as it would for you to jump ten feet straight up into the air? Why or why not?

It would take the same amount of energy, but the second action would require more power, which is work/time.

What, according to special relativity, happens to my alarm clock when I throw it across my room in the morning? Will I be able to observe these effects?

Its mass increases, it gets shorter in the direction it is traveling, and it keeps time more slowly. None of these effects are observable unless the object is traveling at "relativistic" speeds, i.e., speeds that are a significant fraction of the speed of light, so I won't notice anything. I'll feel a lot better, though.

Explain the concept of a "trophic level." At which trophic level are omnivores?

Living things that get their energy from the same source are said to belong to the same "trophic level." Plants, which use photosynthesis, are at the first level, herbivores at the second, and carnivores at the third. Carnivores that eat other carnivores are at the fourth level. Omnivores vary in level, depending on what they eat, and "decomposers" are in a separate category.

Explain the three components of any observation or measurement.

M = V + B + e; a measurement is a combination of the true value of that which is being measured, plus bias in the measuring method, plus chance error. Bias always goes in the same direction, but chance error averages to zero, by definition.

Explain why "magnetic monopoles" do not exist.

Magnetism is produced by all moving electrical charges. An electron in motion around a proton in an atom constitutes a current, just like in a circuit in an electromagnet. Because of this, even if you break a magnet apart down to a single atom, you will still have a current loop and therefore a dipolar mag

Explain the difference between mass and weight.

Mass is the amount of material an object has -- it is a measure of its inertia, of how much force it would take to change its momentum. Weight is the amount of force exerted on a particular object's mass by the gravitational attraction of another (generally much larger) object on which it may be placed.

The atomic number of Magnesium (Mg) is 12. Tell how many protons, neutrons and electrons there are in one atom of 25Mg++. How many electrons are in that atom's valence shell? Explain your reasoning.

Since the atomic number is 12, that is the number of protons. Since the atomic mass is 25, which is equal to the total number of neutrons and protons, there must be 25-12 = 13 neutrons in this isotope. An electrically neutral atom has the same number of protons as electrons. Since this atom is a double-positive ion, it must have two more protons than electrons, and therefore has only 10 electrons. Finally, since there the first two electrons fill the first shell, there are eight to fill the outer, valence shell.

What is the difference between "special" relativity theory and "general" relativity theory?

Special relativity deals with observers who are not accelerating with respect to each other, while general relativity deals with any frame of reference whatsoever

What are speed, velocity, and acceleration?

Speed is distance divided by time, such as "miles per hour." Velocity is speed plus location or direction. Acceleration is any change in velocity.

Give the names of at least six of Earth's tectonic plates.

The book shows these: African Anatolian Antarctic Arabian Australian-Indian Caribbean Cocos Eurasian Hellenic Iranian Juan de Fuca Nazca North American Pacific Philippine Scotia South American

State Coulomb's Law, in your own words.

The force between any two electrically charged objects is proportional to the product of their charges and inversely proportional to the square of the distance between them.

What is a "valence shell"?

The outer shell of electrons in an atom, where it meets and combines with other atoms.

What is a "bit"?

The term comes from "binary digit," and is the basic unit of information in computer processing. It can represent anything that can only be in one of two states (e.g., "off" or "on," "yes" or "no" and so forth).

Explain what S and P waves are and tell why the difference between them matters to seismologists.

These are some of the waves that are produced by earthquakes. P waves are "primary" waves, formed from the Earth shaking up and down. They are longitudinal in nature, and therefore can travel through the Earth's liquid outer core. They are faster than S waves, and so are the first to arrive at a detection station. S waves ("secondary") are caused by the surface moving back and forth, are transverse, and cannot travel through the outer core. They arrive later and have magnitudes different from the P waves. These features allow for the calculation of the earthquake's magnitude and point of origin ("epicenter").

What features are shared by all electromagnetic waves? In what ways might two such waves differ?

They all travel at the speed of light and the need no medium through which to travel. They can differ according to wavelength and frequency (and therefore energy).

Write the equation for a graphed line, and explain its terms.

Y=mx +b. Y is the value of the dependent variable (vertical axis), x the value of the independent variable (horizontal axis), m is the slope of the line (rise/run or dy/dx), indicating the rate of change, and b is the "yintercept" where the line crosses the y-axis (x=0).

A race car completes a 2-mile oval track in 58 seconds. Did the car accelerate during those 58 seconds? Why or why not?

Yes, it did accelerate, even if it ran at a constant speed, because it turned around the oval track, and a change in direction is also a change in velocity, which is what acceleration is.