Universal Laws

When you think about it, everything has rules, from the smallest atoms to the universe itself. Some of the main rules that govern our very existence (whether or not they are evident in our daily life) are gravity, Newton’s Laws of Motion, and Kepler’s Laws of Planetary Motion.

A force is defined as any push or pull on an object, and gravity is perhaps the supreme force: anything that has mass exerts a gravitational pull. Gravity was the guiding hand behind the formation of our solar system, according to solar nebula theory. This hypothesis states that, after the star of whose guts we are made exploded, gaseous clouds coalesced around a central mass that was to become our sun. The sun’s gravity caused it and the surrounding protoplanets to spin, and our earth’s orbit has continued to this day.

The iconic image of Sir Isaac Newton catnapping against a tree shortly before an apple fell on his head and sparked his “discovery” of gravity may not be entirely accurate, but he did an excellent job of summarizing this unseen, mysterious force. Newton’s first law, the Law of Inertia, states that “An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.” This is easily demonstrated: take an stationary object--a soccer ball, perhaps. When placed on a field, the ball does not move: gravity pulls down on the ball, but the ground pushes back with equal force. The second law says that “The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object,” which is often transcribed, more comprehensibly, as a=Fnet / m, or Fnet=m×a. This is clear in that the same amount of force applied to two objects, one large and one small, will produce a greater  acceleration in the smaller object. Newton’s third law says that “For every action, there is an equal and opposite reaction.” Picture two people leaning on one another. The forces each of them is exerting on the other are balanced. Now (in your mind) replace one of the people with a brick wall. Although it may not be obvious, the forces are still in balance, and the force the person exerts on the wall is equalled in the wall’s resistance to it.

In close relation to Newton’s Laws are Kepler’s Laws, which deal with motion on a somewhat larger (but more fixed) scale: the scale at which the planets in our solar system revolve. Kepler’s first law is the Law of Ellipses, which explains that planets orbit the sun on a path in the shape of an ellipsis, a special figure formed that the sum of the distance from any one point to two foci is the same. In simpler terms, the planets’ orbits are oval-shaped. The second law is the Law of Equal Areas, stating that, though a planet’s speed fluctuates depending on its distance from the sun, if imaginary lines are drawn from the planet to the sun at regularly spaced intervals in time, the figures formed will have the same area. Kepler’s last law is more numerical in nature. His Law of Harmonies, a comparison between the orbit period and orbital radius of a planet, shows that the ratio of the squares of the periods to the cubes of their average distances from the sun is the same for every one of the planets.

Thermal Energy & Heat Transfer Intro

The most recent activity in our class has been exploring the science behind thermal energy and heat transfer. Our next few posts will cover our examination of an old farmhouse as apprentice energy auditors and our first forays into the field of engineering and design.

Let’s begin with some basic terminology and principles fundamental to an understanding of the processes by which heat is transferred. First and foremost, “heat” is a common term for “thermal energy.” Thermal energy is transferred, generally speaking, through one of three methods: conduction, convection, or radiation. In conduction, heat travels through a solid material, passing along its energy at the molecular level. We say certain solids (mainly metals) are “conductors” if they have an above average ability to transfer heat in this way; conversely, “insulators” (such as glass, porcelain, and wood) do a poor job of transmitting or spreading heat. Convection is the process by which thermal energy transfers through a liquid or gas. This type of energy transfer is all around us: when we use a fan, boil water, or heat the house with a woodstove, we are taking advantage of one way in which heat travels. A common misconception about heat transfer is that, as people often say, “heat rises.” This is not the case. Heat spreads in all directions, but heated material expands, becoming less dense, so heated material rises. To return to one of the examples above, when we place a pot filled with water on a stove burner, conduction heats the water through the bottom of the pot. (Again, metals are conductors.) Then convection currents form as the water begins to gain energy. The heated water rises through the surrounding liquid, bringing some of its heat with it. At the surface, even more heat is transferred, until the now-cool water returns to the bottom of the pot and the process begins again.

Radiation is the process by which heat travels through the vacuum of space. For example, we receive energy from the sun in the form of solar radiation. An important thing to note is that, while it is possible to stop radiation by insulating with a solid, liquid, or gas or to stop convection and conduction with a vacuum, there is no known method that will completely halt heat transfer. Heat always travels from hot areas to cold (or from areas of energy to those of less energy), and it can only be slowed. That is the main goal of an energy auditor when making modifications to a house to improve its energy efficiency.

The process used  for an energy audit begins with knowledge of insulation. In professional circles, the ability of an insulator to resist heat is measured with a unit known as “R value.” A higher R value indicates better resistance to heat. Old houses are prone to cracks and  drafts from years of inhabitation and renovation. Most heat loss is incurred from convection at the top and bottom of the house: the attic lets heat escape, while cold air seeps in through the basement.

Continental Drift, Plate Tectonics, and their Unseen Impact on Earth

For centuries, scientists held the belief that the continents were fixed in their places. About a hundred years ago, however, someone came along to completely revolutionize this and set a foundation for the theory of plate tectonics.

This man was Alfred Wegener, a German meteorologist who observed that many of the continents seem to fit together like puzzle pieces. For example, the coasts of South America and Africa are like a newspaper page ripped roughly down the middle. Furthermore, Wegener discovered that rock formations and fossils in these areas and others of the colossal continental puzzle match up in surprising ways. The main pieces of fossilized evidence for continental drift are the mesosaurus and glossopteris, a lizard-like freshwater animal and a fern found as fossils across continents with no means of being easily transferred.

There was only one problem with this theory, which Wegener termed ‘continental drift’: he had no mechanism for movement--that is, Wegener lacked an explanation for the ‘drift.’ He hypothesized that the continents floated on the ocean, which is a laughable suggestion even today.

However, all of the evidence for continental drift still applies to a new theory, developed around the 1960’s: that of plate tectonics. This idea elaborates on continental drift, providing both new evidence and a mechanism for movement. Plate tectonics shows that the lithosphere is broken into pieces. These plates ‘float’ on the denser asthenosphere (the lower mantle). Recent advances in science, such as sonar and satellite data, have allowed scientists to view the earth and its plates in new ways. Revolutionary imaging techniques let us see that the age of oceanic crust increases farther away from divergent boundaries (where two plates move away from one another)--young oceanic crust forms at these borders. Another piece of evidence is ‘magnetic striping,’ which shows that the earth’s magnetic field reverses every few million years and the iron in new crust formed at divergent boundaries conforms to its direction.

There are other, more obvious effects of plate movement: they cause both volcanoes and earthquakes. One of the most devastating (and least recognized) volcanic eruptions ever recorded occurred on April 9th of 1815, when the Tambora volcano erupted over Indonesia. Though some of the ramifications were immediately obvious--a “death toll was around 100,000 people from the thick pyroclastic flows of lava; the tsunami that struck nearby coasts; and the thick ash that blanketed Southeast Asia’s farmlands, destroyed crops, and plunged it into darkness for a week”--others were more lasting, and have only recently been investigated properly (D'arcy Wood, 2014).

For several years following the Tambora eruption, the land was plagued by drought, disease, floods, and famine, but this was just the beginning. The gases released in the eruption went on to interfere with the Indian monsoon, give rise to a new, deadly strain of cholera (which “shaped the 19th century like no other calamity” as it spread across the globe), force disaster on Chinese farmers so extreme that they sold their children before turning to opium as a crop of choice, cause ‘the year without a summer’ and the ‘Panic of 1819’ (both of which impacted the US), and melt enough sea ice around Greenland and the Arctic that the British could found the age of polar exploration (D'arcy Wood, 2014)...  And this massive impact was all rooted in an innocent plate boundary in the East Indies. What if something like this were to happen again? Another eruption that would be remembered for centuries to come…

Bibliography

D'arcy Wood, G. (2014, April 9). One of the Most Devastating Volcanic Eruptions in Human History Just Got Even Worse. Retrieved April 17, 2014, from http://www.slate.com/articles/health_and_science/science/2014/04/tambora_eruption_caused_the_year_without_a_summer_cholera_opium_famine_and.html

http://discovery.yukozimo.com/media/o/3750-2.jpg

http://eatrio.net/wp-content/uploads/2013/01/8.-pangea_07sep2007.jpg

http://cookwilkie11.wikis.birmingham.k12.mi.us/file/view/magnetstripes2.jpg/294996626/magnetstripes2.jpg

Age of earth's oceanic crust (in millions of years) [Digital image]. (n.d.). Retrieved April 26, 2014, from http://media-2.web.britannica.com/eb-media/84/99284-004-1976F092.jpg

Earth's History

Earth formed roughly 4.6 billion years ago as a molten sphere of rock clouded with “choking fumes” (Appenzeller 2006). With time, the young planet cooled, and, as it became more hospitable, life slowly emerged, triumphing over several extinctions in order to achieve its current state of a flourishing, diverse environment. Earth is at an ideal distance from the sun, so that it retained water while it cooled; water is a critical ingredient in life. Three point eight billion years ago, the first life emerged as photosynthesizing cyanobacteria. It took another 3.256 billion years until the Cambrian explosion, the time period where most fossils originate from. With the beginning of the Paleozoic era came a time of dramatic geological, climatic, and evolutionary change. Interspersed with various advancements in the sophistication of life were five extinctions--the Ordovician (445 million years ago), Late Devonian (360 million years ago), Permian (251 million years ago), Triassic (205 million years ago), and K-T (65 million years ago). During each extinction, huge percentages of life were eliminated. However, that which was left (at times only 5%) rebounded, shaping today’s world after the first hominids appeared 4 million years ago.

For a more in-depth exploration of Earth’s History, please view our Prezi here.

Our bibliography is here.

Opinion Piece: Should They Suffer in Silence?

Is it our responsibility to help countries suffering from the effects of global warming?

In my opinion, it is the responsibility of not only this country, but all the world’s people, to help countries suffering from the effects of global warming. Those in the poorest countries, which have made the least contribution to climate change, have been and will continue to be the most impacted by the seemingly unstoppable terror that is global warming.

The main sources of stress caused by climate change are the rising sea waters and the pressure it places on the agricultural industry. Many small nations with a poor economy, such as the Philippines and Malaysia, are facing posed by the ocean when one lives mere feet above sea level. Additionally, the food supply is being thrown off-kilter by slowly increasing global temperatures and a lack of fertile soil--some of which is being swallowed by the seas.

If we trace global warming back to its roots, we find that the countries which shifted towards industrialization the earliest have contributed the most. For example, the US had its first Industrial Revolution in the mid 1800s, and since then has continued to be a main source of CO2 pollution. As the country now attempts to cut back on emissions and find a reliable, ‘clean’ energy source, other countries’ growth ( read: China) have overpowered our comparatively weak counterattacks. So now we say, “Well, this certainly must not be allowed to continue.” We turn to small countries like the Philippines: “Hello! You--yes, you. Don’t industrialize.” And they’re all like, “What? Oh no, that is not fair. You got us into this mess--what are you going to do to get us out??” And so, regardless of certain countries’ justified, but minor, outrage, aiding poor countries is an ethical issue.

Now, the issue that I have not addressed yet is this: How do we intend to fix this mess? We have our own problems! And yes, that is true. But: Can you honestly stand aside while innocent people, who struggle to get by on a daily basis, are forced out of their homes into a cold, unfeeling world? Can you tell me there is nothing we can do about this? And if these people do lose their homes, where will they go? They can move in with you--or they can be another drain on our tax dollars and honest income. I will only say this: There is always something you can do, something you can stretch, and, if you do lend a hand, you will find that it isn’t at all that hard.

Opinion Piece | Nuclear Fusion: Future or Failure?

Through our discussions (between the three of us) we have come to an agreement that nuclear fusion, though costly, is well worth the money in an attempt to climb out of the hole that has been caused by the world’s rapid consumption of energy.

Electricity and other forms of energy are crucial to the smooth function of our everyday lives. However, we often forget the cost of our consumption. For example, electronic devices, though portable, require charging and use energy through chargers. Lights on and off throughout the day and night leads to not only a high energy bill, but with that a high energy consumption rate. People perform these tasks (plugging in a charger and flipping on a charger) mindlessly, thus leading to an energy crisis. This is where nuclear fusion comes in; though the cost is extensive, so are the benefits. Once the energy is created and dispersed, the energy will be available and also earth friendly. That is why we have agreed that nuclear fusion is worth the cost and effort.

Nuclear Fusion in a Nutshell

Summary of "Star in a Bottle," by Raffi Khatchadourian

In about a decade, the International Thermonuclear Reactor, or ITER, will be complete. This machine, the most complex ever built, will be located in Southern France. Inside of ITER, such intense heat and energy will be released that it will have to be restrained by a so-called ‘magnetic bottle.’ By the time the production of ITER comes to a close, a total of 35 countries will have invested eight years of energy and a approximately twenty billion dollars. When ITER creates energy using nuclear fusion, it will, ideally, produce next to no pollution and serve as an accessible means of producing energy for years to come. Despite this tantalizing vision, the largest downfall this international project holds is the cost. Those funding and supporting the production of nuclear fusion energy will need to have thought long and hard about how much money is worth the end product.

Third Experiment: Forensics Lab

Lab Design Sheet

Name of Experiment: Murder! (Who did it? A forensics lab)

Prior Knowledge: On March 6th at 3 am, an assistant baker at Mike’s Awesome Bakery in Francestown, NH was found dead lying in a pool of blood. The assistant baker was found covered in a mysterious white powder, which our Earth Science class must identify.

Investigators collected samples of white powder they found in the bakery (baking soda, baking powder, flour, cornstarch, and the unknown substance found on the body).

As well as collecting substance samples, the investigators interviewed employees of the bakery and took clothing samples to see if any employee had traces of the substance on their person.

Objective: Identify the unknown substance

Equipment:

• baking soda
• baking powder
• flour
• cornstarch
• unknown
• vinegar
• iodine solution
• universal indicator
• water
• lab materials (beakers, stirrers, pipettes, etc)

Procedure:

1. Arrange materials
1. Collect samples of baking powder, baking soda, flour, cornstarch, and the unknown substance along with a plastic-covered data sheet
2. Collect five Popsicle sticks and four pipettes, one each for water, vinegar, iodine, and universal indicator
3. Line up corresponding substances with Popsicle sticks placed above their columns on the data sheet
4. Use corresponding Popsicle sticks to spoon small piles of each substance onto the data table
2. Test baking soda
1. Test reaction with water
1. Squeeze 3 to 5 drops of water onto the baking soda with a pipette
2. Study and record the reaction
3. Repeat steps 2a to 2b with vinegar, iodine, and universal indicator
3. Test baking powder
1. Repeat step 2 accordingly
4. Test flour
1. Repeat step 2 accordingly
5. Test flour
1. Repeat step 2 accordingly
6. Test cornstarch
1. Repeat step 2 accordingly
7. Test unknown
1. Repeat step 2 accordingly
8. Clean up materials
9. Analyze collected data
10. Finalize conclusion and complete lab sheet

DATA:

	Baking Powder	Baking Soda	Flour	Cornstarch	Unknown
Water	NO REACTION	CHEMICAL REACTION: Mixture fizzes/ bubbles	PHYSICAL REACTION: Water runs off, mixture becomes glue-like	PHYSICAL REACTION: Changes texture, becomes tacky	CHEMICAL REACTION: Mixture fizzes/ bubbles
Vinegar	CHEMICAL REACTION: Mixture fizzes/ bubbles, vinegar consumes baking soda	CHEMICAL REACTION: Mixture fizzes, but baking powder is more resistant to vinegar than baking soda	NO REACTION	NO REACTION	CHEMICAL REACTION Mixture fizzes and grows
Iodine Solution	NO REACTION: Iodine does not change color	CHEMICAL REACTION: Some bubbles; mixture becomes a dark purple/ indigo, lightens	CHEMICAL REACTION: Mixture becomes a gray/navy/ purple color	CHEMICAL REACTION: Mixture becomes a dark indigo, then lightens	CHEMICAL REACTION: Some bubbles; mixture becomes a dark purple/ indigo, lightens
Universal Indicator	CHEMICAL REACTION: Teal/green color becomes blue; no movement; pH 9	CHEMICAL REACTION: Red to orange to yellow to green; pH 7?	CHEMICAL REACTION: Orange color; pH 4	CHEMICAL REACTION: Pinkish-red color; ph 3	CHEMICAL REACTION: Orange to yellow to green; pH 7?km

CONCLUSION: The investigators should be looking for baking soda on the suspects' clothing. We determined this by comparing the presence, type, and details of each substance's reaction with water, vinegar, iodine, and universal indicator. Both baking powder and the unknown had a chemical reaction with every reactant that we tested; this was not the case for any other prospective substance. Additionally, the pH was the same between baking powder and the unknown, and the details were the same for every other reaction.

Second Experiment: Mixture Separation Lab

Lab Design Sheet

Name of Experiment: Mixture Separation

Materials

• Canister filled with salt, sand, and iron filings
• Beakers
• Magnet
• Plastic bag
• Coffee filters
• Hot plate
• Triple beam balance
• Glass stirrer

Procedure:

1. Arrange materials
1. Find the mass of the substances in the canister and record it
2. Separate iron
1. Use the magnet in the plastic bag to attract the iron filings
2. Pull away the magnet inside the plastic bag to let the filings fall onto an empty coffee filter
3. Repeat to filter out sand and salt
4. Find the mass of the iron filings and record it
3. Separate sand
1. Add a small amount (about 50 mL) water to a beaker
2. Pour in the salt and sand mixture
3. Stir to dissolve salt
4. Strain through a coffee filter into another beaker to separate saltwater and sand
5. Allow salt to dry out
6. Find mass of sand and record it
4. Separate salt
1. Place beaker with saltwater onto hot plate
2. Turn hot plate to high to boil off water
3. When water has boiled off, find the mass of the salt and record it
5. Clean up

First Experiment: Floating Paper Clips

­Lab Design Sheet

Name of Experiment: Floating Paper Clips

                             

Question to be answered: Is it possible to make paper clips float by bending them at a 90 or 180 degree angle?

Prior Knowledge: We read on the internet here that if paper clips are bent at a 90 or 180 degree angle then they should float in water. However, we also know that paper clips are more dense than water and should, therefore, sink.

Hypothesis

Prediction: If a paper clip is bent at a 90 degree angle, then it will float…

Rationale: … because the bent portion of the paper clip is used as a stabilizer and the amount of its surface area in contact with that of the water is reduced.

Variables

Independent variable: The shape of each paper clip.

Dependent variable: Whether the paper clips sink or float based on their shape.

Constants: Same beakers, amount of water, and brand and size of paper clip; where/how we drop the paper clips; we will use gloves to prevent the oils on our skin from coming in contact with the paper clips.

Equipment:

• Three 500 ml beakers,
• 400 ml of water,
• Twelve paper clips (6 large without plastic coating and 6 small with plastic coating), and
• Rubber gloves.

Procedure:

1. Set up materials
1. Arrange equipment
2. Fill all three beakers with 400 ml of water.
2. Bend paper clips
1. Put on gloves
2. Bend 2 “plain” or “large” paper clips to 90 degrees and bend 2 “plain” paper clips to 180 degrees, leaving 2 unbent
3. Repeat bending process with “small,” plastic-coated paper clips.
3. Execute experiment with large paper clips
1. Drop 1 unbent paper clip into a beaker from a height of 5 cm
2. Repeat once for each remaining paperclip shape, reserving a beaker for each shape
1. Record results
2. Remove paper clips from beakers and replace any spilled water
3. Repeat with remaining large paper clips
1. This time, paper clips should be placed in the water
2. Record results
3. Remove paper clips from water
4. Execute experiment with small paperclips
1. Repeat above steps with small or “plain” paper clips
5. Clean up
6. Record and analyze results

DATA:

paperclip	unbent	90 degree angle	180 degree bent
large 1	fail	fail	fail
large 2	fail	fail	fail
small 1	fail	fail	fail
small 2	fail	fail	fail

ANALYSIS: We attempted to make paper clips float by bending them at various angles. According to an online source, paper clips bent into a right or straight angle should float on water. However, our experiment was unsuccessful; all of the paper clips, in various configurations and sizes, sank.

CONCLUSION: The paper clips did not float because the surface tension of water is not great enough to support such dense objects. The information found online was inaccurate or did not reliably portray the means by which a paper clip can be made to float. If we were to return to our hypothesis, two possible ways to change the outcome would be, first, to use entirely plastic paper clips, as these are less dense than metal or partly metal paper clips; and, second, if the first strategy was unsuccessful, to float both metal and plastic, bent and unbent, paper clips in salt water because salt water is more buoyant than regular water. As a last recourse we could use a tissue to float the paper clip, which is another method found online.