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Posts Tagged ‘Science’

Heat acts like an invisible fluid that washes over and penetrates through any barrier. The reason I thought about it this morning was the temperature in the house, the difference in temperature from outside, and the feel (comfort level) in the house.

The thermometer, placed on the counter in the center of the house, said 68 degrees, which is a reasonable indoor temperature. But should I start a fire in the stove? Ultimately, for most people, the answer to that question depends on comfort level. Ignoring the real psychological components of comfort level, comfort level depends on heat flow rate.

Heat flow rate is the reason for heat index and chill factor in weather reporting of temperature. An inanimate object feels neither extra hot when it is humid nor extra cold when the wind is blowing. The temperature at which it settles is determined solely by the average rate of vibration of its molecules (i.e. temperature). 

But when an object like a thermostated heater or warm blooded mammal or human is warmer than its surroundings and produces heat to maintain that difference, heat flow rate is crucial to comfort and even survival.

For a fuller understanding of this concept. let us posit two facts:

  1. Heat always flows from warmer to cooler.

  2. Heat Flow Rate is     Screen Shot 2018-12-08 at 6.05.10 PM,

where Q is heat, t is time, K is conductivity, dT is change in temperature, and l is length (distance or thickness) of heat flow, and the combination of dT/l is the temperature gradient.

Since in winter I heat with wood for the purpose of keeping us warm and feeling warm, I will consider the situation of heat flowing out of our bodies. Unless I am sitting by the woodstove, I am warmer than the room and heat is leaving me.

The greater the area (A) of my skin exposed to the surroundings, the faster I cool off. For this reason, you don’t expose flesh to the air on an extremely cold day because the heat flow rate is so great from any area of  your body that it can’t provide enough heat to prevent your flesh from freezing.

The greater the temperature difference (dT) between me and the environment cooling me, the faster I cool off. Our bodies are constantly radiating heat to the cooler surroundings. If you have ever worked in an unheated building with a concrete floor, you know that it is very hard to keep warm. You can feel the concrete zapping heat out of you (you radiating to it, in fact).

The shorter the distance (l) for the heat to flow to reach the cooler temperature, the faster I cool off. The thickness is the reason thicker insulation works better. More thickness of a substance that slows heat flow rate slows it more. Insulation, be it pink or down or quilt is really just a function of how much non-convecting air is trapped in the insulating layer. Air is an excellent insulator, which brings us to the next component.

And the better the material is at conducting heat (thermal conductivity (K)) off of me, the faster I cool off. Conversely, the reason air is poor conductor of heat is the distance between molecules. On the other hand, since it is a fluid, it is a decent convector (heat transfer by flow of a fluid), and it provides little resistance to radiation, since there is less matter than most materials to absorb or radiate back the heat. When you put a warm hand on a cold, wooden table it won’t feel very cold, but on a cold, metal appliance it will. This increased flow happens because the metal has a far greater thermal conductivity than an insulator like wood.

Soooooo, back to my question. Should I start a fire when the core of the house is 68 degrees? Considering this situation, I ask myself several questions. What is the temperature outside? Is there a strong wind cooling the house? Is there cloud cover to prevent cooling at night or prevent warming during the day? Is there a temperature trend up or down from the present reading of 68 degrees because of internal or external changes to the house? About this time, those of you who have thermostats that do all of this “thinking” for you should stop taking it for granted. It is a relatively old technology, but not an altogether simple or trivial one.

In terms of comfort level, it can be 68 degrees in the core of the house and feel quite chilly because the outside is removing heat rapidly. This situation will result in the peripheral (near the outside walls) temperature being several degrees cooler.  I used to have my indoor/outdoor thermometer on a window sill. It consistently read cooler than the one I have now. My new thermometer wouldn’t fit on the sill. It would probably be easier to not think about it if I had a thermometer in the center of the house and on the window sill. Then I would have an approximation of the heat flow rate out of the house, but that would make me less truly aware of my surroundings. I have to walk past the central thermometer and past the window to get to the refrigerator and the stove to make my breakfast anyway, so I feel the temperature difference from core to periphery. I do not, however, usually think much about the various components of heat flow rate, because I am only barely awake at 5:15 in the morning.

101_1604

Not time for a fire, yet (I need to reset the clock.)

P.S. If you read this far, I surmise that you are either a science geek or a particular friend. Either way, thanks for reading, and glory to God for His ordered universe and minds to make sense out of it.

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About five years ago one of my classes built two bluebird boxes to put just out the window of two classrooms at the school. One lasted one year and then got taken by vandals. The other one outside my window could be destroyed but not so easily taken because of the wiring that runs out the bottom of pipe pole, through concrete, underground, through the wall into my classroom and to my computer. I realize that wireless cameras exist, but this is what my students could afford. It is color, works at night by shining infrared lights, and has sound. At one time you could record segments of video, but the school techs lost the software that has to be reinstalled every year due to computer re-imaging.

There are two problems with the present set-up. Even with retreating the wood, five years is considerable weathering, so the roof piece is bowed and lichen encrusted, though still functional. The other problem is a matter of rushed planning on my part when it was built. The students were excited about the camera arriving; the box was already built; we quickly installed it and began observing nesting soon afterwards. The camera, however, was mounted too close to the subjects so that it has always been blurry. The new box has a ceiling below the roof where the camera will be installed and not susceptible to moving when the side panel is opened to clean out last year’s nest. The distance is increased sufficiently to enable in focus viewing.

Since there are three eggs in the present box now, the installation of this new box will wait until Fall or later. I had the time to build it now and the availability of the school shop, so I did. I may put a roof shingle on the top when I install it so that it will last more than 5 years.

Students totally love to see the progress of the birds building a nest, laying eggs, hatching, feeding, growing, and leaving the nest. They are amazed when they here the chirping, chagrinned when there is a runt that is underfed because the others poke their heads up faster and more consistently, and curious about gestation and developmental timings. We have 2 to 3 nesting each Spring. One year the bluebirds and tree swallows fought violently over which pair could nest first. At one point two males (one bluebird and one tree swallow) were rolling around on the ground, clawing and pecking. The students flew to the window to see what was happening. We have never been able to observe the hatching of the birds. It seems to always happen on the weekend or in the early morning. I have left at 5 PM and arrived at 7 AM the next morning to find several birds hatched.

I sincerely wish that I could do more of this kind of teaching, what I call “affective science”. Students need an emotional connection to what they are learning to prick and increase curiosity. I could give many reasons why this is not happening, but I’m not in the mood to wax political or negative, so I will leave that to your imagination. I recorded some aspects of the box build, but many details are also left out. I hope that you enjoy the pictures, but even more, I hope you will observe the world around you and give thanks to our Creator for its utter beauty and utility.

If you hover over the pictures, you can see the captions.

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Science is a great tool for exploring the world. It saddens me that it has so much been commandeered for purposes contrary to the truth of God’s Word. Many of the processes discovered and described by scientists accurately align with observable reality, but particularly on the subject of time scales, their tomes do not ring true to what is verifiably true from Scripture or nature. I choose to believe what the Bible says over the faith system based on time, chance, matter, and energy. I think that it takes greater faith to worship these inanimate gods. So, I like to discuss weathering, for instance, but I reject uniformitarian time scales based on my faith and the field ‘evidence’ tendered (see 4th paragraph of “Four Singularities”; 3rd paragraph of “Amazing, Credible, Scientific Point of View”; “Many Grand Canyons”).

While teaching Earth Science, we discuss weathering at length. As with any study, teachers and students categorize subject matter. This frequently separates ideas that would naturally be together if organized in another way. For instance, is weathering a subject to be initiated and discussed in geology, hydrology, meteorology, or oceanography? It should be discussed in all of these areas of study, including astronomy (evidence of erosion on Mars, for example) and ecology (interaction biotic and abiotic factors in soil formation and fertility, for example). Where it is initiated is a bit harder. Do you begin during discussion of the rock cycle, or when you explain formation of soils, or when the main agent, water, is acting upon rock? I have chosen to mention it during oceanography, hydrology, and minerals and rocks units, but devote a separate unit to weathering and erosion by fleshing out the details of “WETS”: weathering, erosion, transportation, and sedimentation, and also soil formation. I repeat these concepts many times during the day and from semester to semester. Along with the hazards of plate movements, I guess the ocean part of change got to me, resulting in the following poetic outworking:

Wave upon wave upon the coast breaks
Battering and bludgeoning the shore
Each grain of sand that it takes
Builds a beach or a bar or seafloor

Longshore currents carry sediments
Outsourced from the rivers and headlands
Man-made wall impediments
To the flow of the nourishing sands

In deltas and mangrove swamps land grows
Protected from tidal surge and wind
Barrier isles resist flows
From storm surges and tsunamis that rend

Estuaries were once rivers
Where now the brackish waters are mixed
Fjords formed where one shivers
By ice scouring hard rock once fixed

Island arcs form in convergent zones
Some are explosive in the extreme
Subducting ocean plate groans
Hydrothermal vents with strange life team

From hot spots and boundaries they grow
Deep under water, volcanic mounts
Up from the mantle below
Convective cells produce magma founts

Some seamounts are flat on top
Belying once shallower sea wave
Blue hole a flooded cave drop
Once air filled, now a watery grave

Mid-ocean ridges build ocean crust
Plates transform by seismic shear stress
Others earthquake megathrust
Oh, so much crustal strain and duress

So much building up and tearing down
Reveal beautiful changing landforms
Hard to see, so much is drown
But wear, change, and movement are the norms

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Wet?

I most dislike annoying little problems when I have previously tried to solve them to no avail. Or even worse when my ‘solution’ works for a while and then doesn’t. I bought a non-stick, copper infused, ceramic skillet (“Red Copper’ brand) about 6 months ago so that my wife and I could cook our breakfast without it sticking. For about 4 months it worked wonderfully. Undercook, overcook, oil, no oil, it didn’t seem to matter, it didn’t stick.

My wife makes homemade sausage and almond meal pancakes. So my daily procedure is to put a little oil in the pan, add crumbled sausage, break two eggs over it, scramble the yokes, and move away to put a pancake in the toaster and pack my lunch. Just before the egg is totally solid I turn the eye off and flip the egg-sausage fritter over, reaching over to push down the toaster button.

Why did it begin sticking when I try to flip it over? It didn’t for several months and now it has for several months. I set out to try to figure out this mystery. I must be doing something differently. That the change resided in me and not in the pan was clear to me from two additional pieces of information. My wife cooks her breakfast after I have left for work. She commented one day, “Why are you having trouble with the food sticking in the pan? Aren’t you using oil? Mine doesn’t stick.”

Secondly, I re-oiled the pan like I had when I first got it. You fill the bottom with oil, place it in the oven for 15 minutes at low heat, and pull it out to cool. I could see why this works, because it reminds me of oilite bushings. Wikipedia says, “Oilite is a porous bronze or iron alloy commonly impregnated with an oil lubricant and used in bearings.” When the bearing warms up during use, it will release a little oil that lubricates the bearing surface preventing overheating. It works wonderfully well and the bearing can be re-oiled by submerging it in hot oil. But that didn’t prevent the egg from sticking.

I tried more oil. The liquid egg only pushed it aside and stuck to the bottom.

I tried different kinds of oil: butter, olive oil, coconut oil. The smells were great but the sticking persisted.

I tried different temperatures which either left me twiddling my thumbs or the egg slightly burnt on one side.

Finally, I pretty much gave up, but the egg pushing the oil aside confused me a bit. Why didn’t the egg just roll over the top of the oil as it cooked? I realized that the real question that I was asking was, “Why does the oil not wet the surface of the pan but the egg does?”

For many of you the word “wet” seems totally out of place in this scenario. Afterall, waters wets, right? But what does it mean to wet a surface? I will give a formal definition in a moment, but the best one is illustrative. Water wets an unwaxed car but beads up on a well waxed car. Water is sticky. It adheres to things different than itself, that is wets surfaces, and it coheres to other water molecules, that is beads up. So how does it decide which one to do? If the adhering forces are stronger, then it wets the surface; if the cohering forces are stronger, then it beads up. Once again Wikipedia (Hey, I’m not into this, you can’t trust Wikipedia thing. Be a bit skeptical of it on religion or politics and realize it will probably be incomplete on many subjects, but as an overview it is a good, quick reference.): “Wetting is the ability of a liquid to maintain contact with a solid surface, resulting from intermolecular interactions when the two are brought together. The degree of wetting (wettability) is determined by a force balance between adhesive and cohesive forces.” All liquids can wet surfaces: water, oil, egg, lava, alcohol, gasoline, and so forth.

The various oils (butter, olive and coconut oils) were beading up on the pan. So, this very morning I tried a new strategy. I let the coconut oil heat until it began to bubble, then I threw in the sausage and egg. It didn’t stick, what a pleasant, small blessing! Perhaps I had become too efficient at making my breakfast in the morning, being so fast at putting in the oil, sausage, and egg, until I had reached the ‘sticking’ point of the procedure. One little, almost imperceptible change I made was putting in those three things instead of punctuating the oil heating with putting in the pancake and opening the almond butter jar.

It will be interesting to see if I have found the real solution. As researchers like to say, “further research is needed.” But I think that upon reflection this must be the solution. My wife always puts in some combination of peppers, onions, and mushrooms to momentarily saute before adding her beaten egg, and her breakfast never sticks. 

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I have the privilege (really!) to patrol Monday morning parking lot duty from 7:15 until 7:50. On most Monday mornings there are no more than 2 or 3 cars in the parking lot when I arrive. That makes for some quiet moments to consider the day, pray about concerns, and look around. Quiet allows you to observe better. One morning I saw various seeds under the trees: Bald Cypress cones, acorns, and Sweet Gum balls. Another morning I saw oak leaves of various sizes and broadness on the ground. Looking up into the tree I could see that smaller ones generally came from the top of the tree and larger ones from the bottom. These larger ones are called shade leaves. They are competing for the sparse sunlight in the shade cast by the rest of the tree. Yet a third morning I spied leaves popping up a few at a time in the direction from one bush to another. I kept watching and every 5 to 10 seconds the leaves would pop up an inch or so. After every few minutes the movement of the leaves would retrace the path back toward the first bush. I concluded that I was seeing a mouse or other vermin forging a tunnel just under the leaves and mulch on this frosty morning.

Speaking of frost, the very next week the morning was even colder, around 27 degrees (-2.8 degrees Celsius). As I approached my usual vantage point for watching cars, students, and nature, I saw that the golden brown Bald Cypress needles had fallen to the ground in the last week and this morning were fringed in frost. I went to investigate and caught a hold of an early arriving former student, requesting that he snap a picture and e-mail it to me (gonna have to get one of them new fangled smart phones one of these days).

Bald Cypress needles

The most Exquisite Lace

I retreated back to my self-appointed post. Still there were but few cars in the lot and none nor no one stirring. I glanced over toward the frosted needles once or twice. Then between two bushes I spied a curious sight about which I was at first incredulous. In fact, a few minutes later a student came to pass my way and I requested the use of her young eyes to see if she would see what I think I was yet seeing. She confirmed that there were indeed the appearance of heat waves between the bushes. Imagine, heat waves on a frosty morning! She went on and I was left standing to contemplate how this could be. Moments later a small breeze kicked up and the waves were gone. That only served to confirm my belief that they had been heat waves.

Heat waves are caused by varying densities of fluid (air in this case) refracting light passing through them. Usually the warmer fluid is rising, forming a convective cell. As it randomly snakes upward the background images are gently contorted by the light passing through the foreground fluid.

But what was forming the heat waves? As my eyes scanned the parking lot and Cypress needles, it seemed to me that the frost was heavier during the short period I had been standing there. That may have only been to my sight because of the increasing light as the sun rose, but it brought a possibility to mind. When frost forms, water vapor in the air turns directly into solid ice crystals on the grass or windshield. This process is called deposition, which is the opposite of sublimation, and skips the liquid state going either way. The heat given off by changing from gas to liquid and liquid to solid is about 8 times more than the heat given off by the same amount of liquid water cooling from 100 to 0 degrees Celsius. Needless to say, a significant amount of energy is given off by the deposition of frost. Frosty heat waves, that is shimmering amazing.*

*If my conclusion is correct

 

 

 

 

 

 

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Equations are abbreviated definitions that simplify and  clarify complex concepts and data. They may be used to calculate, which may either reveal past events or predict future outcomes. Qualitatively, they enable the understanding of interrelationships between variables, which may not be obvious otherwise. On the other hand, not all relationships within an equation are the mere product of their juxtapositions within an equation. Rather, some variables owe their interaction to feedback loops within their physical situations. For instance, according to the equation below, in order to have the best period (race time), both power and endurance must be at their maximum. But in physical reality, for a runner, when power is maximum, endurance must be low. Sprinters are not endurance runners. Conversely, when endurance is high, then power must be low. Long distance runners are not sprinters. Actually the equation does reveal this relationship, because if you move the power variable to the other side of the equation you get po = 1/e, or more accurately, power is inversely proportional to endurance. That is, as endurance increases, power decreases.

From the equation you may also see that pace and distance should be inversely proportional. But the opposite is true. A longer distance requires requires a slower pace, that is, larger number.

And when distance is increased, endurance must increase and power must decrease.

The Runner efficiency variable may not be able to be determined, though I think that athletic physiologists are trying desperately to do so with VO2 max, respiratory exchange ratio, fast twitch/slow twitch muscle, body mass, % body fat, and running mechanics. Strength training and anaerobic sprints seem to be two popular methods for increasing runner efficiency. Diet must not be discounted as a way to build better runners.

The constant, K, is a factor that converts the other five variables into a race time, T. At this level of development of the equation, it is nothing more than a fudge factor to make five variables equal to the one.

 

Screen Shot 2017-11-14 at 9.14.14 PM

The best race time (T) is what every runner, coach, and spectator is after. Thinking through this equation might help the runner and coach better design training that will secure that result. Are you training for power, the sprint, or endurance, the long distance run? What training regimens do you need to perform to meet these goals? How much is it reasonable to increase both power and endurance? What are the limits of one, given the other?

I feel certain that good runners and their coaches have all of the relationships dialed in, so that an equation seems silly, but I benefit in my thought about running by the simple definition called an equation.

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   A worldview must be able to withstand the rigors of reality. It must match up with truth. If there is no absolute truth, then there is no basis for purpose, moral code, love, or rational thought.

         I believe literally what the Bible says about our origin- created in six literal days approximately 6000 years ago, as separate and fully formed kinds of plants, animals, and humans. This view, which simply takes God at His word, leaves no room for evolution between kinds of organisms, so called macro-evolution. How should a Bible believing individual respond to the claims of evolution? Does evidence overturn the plain reading of Scripture?

         In an online video, “The Making of the Fittest: Natural Selection and Adaptation”, the presenters describe what they believe to be an airtight example of modern evolution: “Thanks to Nachman [the researcher],” says the narrator, “Science has an example of evolution clear in every detail.” Michael Nachman has studied pocket mice on the lava beds of Southeast New Mexico. Based on his population field studies and laboratory DNA studies, Nachman believes that a combination of mutation and natural selection has resulted in the pocket mouse being “evolved to be dark like the rock.” He says, “When a black mouse appears in a white population of mice, that is usually going to be due to a new mutation, and those are random and rare events.” He concludes that studies of the mice at other lavabeds show that “the genetic changes that made the mice black were different in each case. What’s amazing to me is how similar the black mice are…completely different genes. The narrator concludes, “The rock pocket mice show us that evolution can and does repeat itself and why evolutionary change is never ending.”

         But not so fast! First of all, before and after this event they are still pocket mice. Secondly, Nachman assumes that the genes for black fur arose by random mutation. But as Carl Wieland points out in an article about the peppered moths of England:

“Actually, even as it stands, the textbook story demonstrates nothing more than gene frequencies shifting back and forth, by natural selection, within one created kind. It offers nothing which, even given millions of years, could add the sort of complex design information needed for ameba-to-man evolution. Even L. Harrison Matthews, a biologist so distinguished he was asked to write the foreword for the 1971 edition of Darwin’s Origin of Species, said therein that the peppered moth example showed natural selection, but not ‘evolution in action.’”

         Thirdly, a very simplistic understanding of genetics results in only one possible conclusion for how multiple gene variations result in black fur. Given the relatively recent understanding of epigenetics, the better explanation lies in shifts within the expression of genes already resident within the mice. As Marc Ambler says about a different mice study,

“Scientists conducting experiments on agouti mice found that by manipulating nutrition they could switch off a certain gene. When the gene is active (‘on’) the mice are normally obese and a yellowish colour; by switching the gene off the mice are of a normal, slim appearance, and brown. By feeding a combination of nutrients including vitamin B12 to the mother before mating, the gene was able to be turned off in the babies.”

         Bible believer, do not give in to the wiles of evolutionary thought. We know God from His Word and our personal experience of His saving grace, and science supports rather than contradicts that knowledge. Only conclusions based on a naturalist worldview that excludes the need or possibility of God deny His plain communication about who He is and how He created all that we see. Those of you holding to a naturalist view, I challenge you to consider the possibility that God is real and evidence of nature rightly understood points toward Him.

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