I need help! Here are some ideas for upcoming subjects. Please write/post what you would like to discusss and think about.
Radiological dating
Colors (Mr. Land’s demos – the founder/inventer of Polaroid)
Solids, liquids – states of matter
Superconductivity, superfluids
Lagrangian points (note grav of moon vs grav of sun: 57 x 10^3 sun/moon ratio)
Bear constellations & new star
Circular motion
Details on meteors
Details on comets
Posted in Here's Thinking, Introduction
I wrote a year ago or so on this blog about finding micrometeorites in the snow, or in rain, or in just dust falling from the sky. And I talked about that it is estimated that a large fraction of these have iron in them, whereby they can be affected by a magnet.
Since that time, I have probably attempted more than 10 times to find a magnetic micrometeorite in snow, rain, and dust, to no avail. [Actually, I just re-read the previous article and remember I did find one potential particle which accidentally lost in the search.]
I have looked at 1000’s of potential particles under a microscope with a strong magnet moving under the slide in close proximity, and have yet seen one such micrometeorite. There have been 2-3 flat looking magnetic particles which I imagine came from industrial polution, but they did not at all look like photographs of micrometeorites.
On the other hand, I have found probably 100 non-magnetic particles that look like photographs of the micrometeorites – they are black, rounded, and shiny, and in the average diameter I would say was about 1/10 mm.
So, I am wanting to know if others have had better luck in finding them, and what techniques did they use? I am suspicious that some of the “how to’s” I have read were not performed by the writers of those documents.
If you have a reference or an experience to share with me, please respond below or write e-mail to BrightMysteries@verizon.net
Thank you very much.
Boyd
Posted in Uncategorized
David and his bridge that underwent destructive testing in high school
The owl will nest there and lay eggs, she will hatch them, and care for her young under the shadow of her wings. (Isaiah 34:15)
Periodically our son and grandson come to our search the stuff stored in our attic for toys and memories. This past visit, they found a balsa-wood model bridge that my son had built in high school for a classroom contest. I had suggested that the catenary shape might be the strongest shape to use for the weight-bearing parts of the bridge. I left the rest to him.
During the contest, the bridges were subjected to increasing weight until they broke and dropped the weight. He recalls that his bridge came in second, but in a way, was the best one because his design used the least amount of balsa wood – it was light weight but very strong.
What is the catenary shape? It is the shape of the St. Louis Arch and of many ancient and modern arches used in architecture; the shape is most easily achieved by hanging a chain by its two ends. The natural shape it takes between the attachment points is the catenary shape. It is also very close to the shape of the ends of an egg.
While teaching physics, my students showed how strong this shape is. In a simple demonstration two students held a bed sheet between them to act as a catching net. A raw egg (the free-roaming chicken, barnyard eggs are best for this) is thrown hard into the sheet by another student, and, unless the sheet is missed, the egg will not break. At least I never saw it break from hitting the sheet, assuming the catchers did not let it roll off onto the ground.
The other impressive demonstration requires two straight-sided glass cylinders, such as drinking glasses, where one glass will fit closely inside the other. The egg (raw) is padded below and above with a sponge or folded paper towels, for example, and placed in the larger glass.
Important! The egg is placed so the long axis of the egg is parallel to the sides of the glass; in other words, the egg is placed “on end” in the glass. The bottom of the inner glass is then slid into the outer glass until it is resting on top of the padded egg.
Using a chair to steady the person, and standing on a stool about the same height as the nested glasses, he or she gradually places all of his or her weight on the upper glass showing that the egg will support the weight without crushing. Of course, there is a limit of how much it will support. When I last did it, I probably weighed about 200 lbs, and did not break the egg.
Isn’t it amazing, that the law of gravity, as established by the creator, is what causes a chain to hang as it does, that this same shape is that of the eggs laid by various birds and reptiles, and that it forms the strongest type of free-standing arch? Isaiah 34:15 says, “The owl will nest there and lay eggs, she will hatch them, and care for her young under the shadow of her wings.” God loves us and also invites us to abide in His strong shelter.
Posted in Here's Thinking, Physics
“It is the glory of God to conceal a matter; to search out a matter is the glory of kings” (Proverbs 25:2)
In the early days of science, it was believed that there was no connection between electricity and magnetism. The magnetic force was found in rocks with iron ore in them, and then magnets were made by rubbing these special rocks against iron or steel. These were then used to make magnetic compasses, giving a wonderful advancement in navigation.
The early experiments with electricity included the investigation of lightning, made most famous with Benjamin Franklin’s dangerous flying of a kite during a thunderstorm (he and his assistant could have been easily killed by a direct hit). It was also discovered that heat and light could be produced by passing the current from a battery through a thin wire.
However, to show there was no connection between electricity and magnetism, a magnetic compass was placed beneath a wire through which electric current was passed. The equipment was arranged so that the wire was at right angles to the compass needle, thinking that surely if there were a force between them, the needle would be deflected to become parallel to the wire. But there was no deflection.
However, in 1820, Hans Oersted at the University of Copenhagen while preparing this demonstration, discovered that if the compass needle and the wire are parallel to start with, that the needle would swing to being perpendicular to the wire – just the opposite of that which had been predicted. It was a serendipitous moment. He had shown a connection between electricity and magnetism.
This led to the building of an electric catapult, hence the nickname given this force, which today is called the Lorentz Force, named after Hendrik Lorentz who formulated the mathematical equation in 1892 that describes it.
To picture the catapult, imagine a child’s swing scaled down to fit on top of a table. You would use thin wires instead of chains to hold up the “seat” which is also made of wire. Everything would be connected to a battery so that electric current will flow down one “chain”, through the “seat”, and back up the other “chain.”
Directly below the “seat” you would hold a bar magnet with the north pole pointing upward. When the current was turned on through the “swing,” the “seat” would be “catapulted” forward or backward, depending on the direction of the current.
You may have seen toys that swing back and forth tirelessly, run by a single AA battery that is based on this principle. In fact the electrically powered baby swings operate by this catapult force. More importantly this Lorentz Force is what powers electric motors which have played such a large role in the twentieth and twenty-first centuries.
Proverbs says, “It is the glory of God to conceal a matter; to search out a matter is the glory of kings” (Proverbs 25:2) It is such a blessing that He also puts in our hearts and minds the desire to discover these hidden laws of His creation.
Posted in Here's Thinking, Physics
Like the appearance of a rainbow in the clouds on a rainy day, so was the radiance around him. This was the appearance of the likeness of the glory of the Lord. (Ezekiel 1:28)
On our trip to the YMCA today, I asked my grandson why the sky is blue. He said, “Maybe it’s because of the water in the atmosphere.” I replied, “Well that could be part of the reason, but then why is the sky red around the sun at sunset?” He puzzled over that. After a little pause, I gave an explanation and his questions about it helped me clarify the description.
Light, as we described in some articles last year, is made up of small energy bundles called photons. There are red, green, blue photons, and all the other pure colors as well. And sunlight has a mixture of all these colored photons, giving an average to our eyes of white light, or at least it is white in outer space. But our atmosphere affects it in interesting ways.
As the collection of photons of white light passes through the air, the blue photons have about 10 times more chance of being scattered (bouncing off air molecules) than do the red photons. (Today in my research for writing this I found out that Einstein explained this scattering phenomena in 1911 – his contribution to science is amazing, isn’t it?)
Thus the red photons are more likely to pass through the air unimpeded while more of the blue ones bounce off in all directions. Thus when looking at the sky away from the sun, a person will see a mixture of light with more blue photons than red ones, and hence it looks blue – sometimes very blue depending on the sun’s position and the clearness of the air.
On the other hand, as people enjoy a sunrise or sunset, they are looking at the light passing through much more air than when the sun is overhead, so the effect of the blue photons being scattered out is greater, and hence, the direct light from the sun to their eyes or reflecting off the clouds looks red to them.
Why does the moon look larger on the horizon? In fact, it is not larger but is the so-called moon illusion. In fact the width of the moon is exactly the same as it is when it is overhead. On the other hand, the height of the moon on the horizon is actually a little reduced than when overhead, caused by the distortion of the light rays passing through the thicker atmosphere.
There are various theories for the cause of this illusion. The one I like best is that when the moon is near the horizon, our visual system is comparing it to the surrounding scenery, and knowing it is much further away, it seems larger. One article says to “trick your mind out of the moon illusion is to bend over at the waist and look at the moon upside down through your legs” (http://www.howstuffworks.com/question941.htm).
“When the morning stars sang together and all the angels shouted for joy“ (Job 38:7)
I have read lots of theories about what the star of Bethlehem might have been. The proposals range from a comet, an unusual conjunction of planets, or a new star, to an angel glorifying God with enough effulgence to lead the wise men to the house with the Christ child. I admit I like that last possibility – the angel – the best. But if it was not a supernatural event, I would propose another way it could have been.
There are old legends and ancient beliefs that have led to a scenario that seems to fit the story in Matthew 2:1-12. It goes like this. First of all, astronomers certainly knew the difference between stars, planets, and comets, so I think the word here, “aster” in Greek, points to a star, not the other type objects.
The “star rising in the east” fits the belief at that time that when a person was born, a star would rise at that moment on the eastern horizon, and that star would pass directly over the place of birth when it reached the highest point in the sky (about 6 hours later), in other words, would have the same latitude as your birthplace. [ Please note the references for this: many astrology books and web sites - I don't like astrology at all, so I won't recommend a particular one, but a google search on "birth star same latitude as birthplace" will give you a list of them, if you are interested.]
In this miraculous birth of our Savior, I think maybe “His star” suddenly flared brightly – a nova or even a supernova. There are about 10 novae discovered each year in the Milky Way galaxy, while a supernova in a galaxy our size only occurs once every 50 years or so. Either way, the flaring of this star caught the attention of these wise men.
I think it took more than a year from the “discovery” of this star for the wise men to arrive in Judea, based on Herod’s order to massacre all baby boys in Bethlehem who were under the age of two. By the time they got to Judea, the nova or supernova had gotten dimmer and was hard to see, especially around a city with its smoke-producing cooking and heating fires. Once they left the city, they “rejoiced to see the star” in the clearer skies.
The star went ahead of them till it “stood over the place where the child was.” This fits the motion of the star as it crept across the sky that night from east to west, and by “standing” over the house, I think that means when it reached its highest point it was directly over Bethlehem.
One legend has it that the wise men looked down an open well where they could see the star pass directly over their heads, with the star lined up exactly with their own reflections upon the water – proof of the exact latitude of the location of birth.
That is the story of how Bethlehem’s Star could have been “born” (nova = new star) at the time of the birth of Jesus, leading the wise men to Him. We can join with the heavenly host in rejoicing over the good news that our Savior has come!
From wikipedia http://en.wikipedia.org/wiki/Quark
Her eyelids were very heavy toward the end of my recital. She said what she enjoyed most was my animated face as I expressed my enthusiasm for those discoveries. And then she asked me to explain more about quarks, so I thought I would write about them (I pronounce it, like all good Texans, as “quorks”, on which she tried to correct me).
The quark story begins about 50 years ago, when protons, neutrons, and electrons were thought to be the fundamental particles of matter, although other types of particles were being found in cosmic rays and from the high energy accelerators. By 1960 about 24 different “elementary” particles had been found with puzzling properties.
In 1956, Murray Gell-Mann proposed that there were even more fundamental particles named quarks which combined in various ways to make up many of the members of this “particle zoo”, as it was called. In 1968, high energy electrons were made to penetrate protons and showed that there were point-like objects inside the protons that interacted with these probing electrons. The experimenters seemed to have found quarks.
It was decided that a proton is composed of two “up” quarks, each having a +2/3 charge, and one “down” quark with -1/3 charge, where the unit of charge is +1 for a proton, and -1 for an electron. On the other hand, the neutron consists of one “up” quark and two “down” quarks, with a net charge of zero.
And, the theory, which has been supported by experiments, says that all of the various members of this class of particles known as hadrons (now numbering about 33) are made up of six different “flavors” of quarks and their anti-particle twins. The six quarks are named: up, down, charm, strange, top, and bottom.
It seems that the force that binds the quarks together in these various particles is so strong that the quarks cannot be forced apart. This is predicted by the theory, and thus far experiments to split the protons or neutrons into quark components have failed.
Isn’t it fascinating that even with such tiny things as protons and neutrons, scientists are able to find still smaller particles like quarks, demonstrating once again the wondrous complexity of God’s creation.
For you formed my inward parts; you knitted me together in my mother’s womb. I praise you, for I am fearfully and wonderfully made. Wonderful are your works; my soul knows it very well. (Psalm 139:13-14)
You can write Boyd at BrightMysteries@verizon.net
The older I get, the more I enjoy the beauty that exists all around us in the creation. The second time I stood at the rim of the Grand Canyon, after a 10 year gap, I expected to be less impressed than the first time. But again, amazed, I stood there and gazed at it “with bated breath and whispering humbleness,” (thank you, Shakespeare).
I get the same thrill studying a spider web reflecting the early morning sunshine from the tiny droplets of water adhering to it and reading that the Creator gave that versatile creature from 2 to 8 spinnerets to spin several types of silk. For example there is dragline silk, capture-spiral silk, and silk to wrap eggs in; a different silk to wrap victims in, and a temporary silk to help build the web.
Wonderful too are the creations made by God’s children: inventions in technology, discoveries in science, and the beautiful language of mathematics. For example, I get excited about the fractions 1/98, 1/49, and 1/7 (try them on a calculator and look for the patterns in the sequence of digits). My wife is frequently amused by my enthusiasm for numbers.
But she did find the Fibonacci Sequence interesting. It is made up of the numbers: 0, 1, 1, 2, 3, 5, 8, 13, 21, … where each number is the sum of the previous two terms. “O.K. , and where…,” she responded.
“This set of numbers shows up in living organisms a lot,” I continued. “For example, flowers with 3, 5, 8, 13, and 21 petals in blossoms are very common, while other numbers of petals are not so common.
“Look at your hands: 2 hands, each containing 5 fingers, each of which has 3 parts, separated by 2 knuckles. ” And I measured the joints of her index finger, and showed her that the lengths were very close to 2, 3, 5 and 8 centimeters (the 4th bone is hidden in the hand). “Now that,” she said, “really is neat.”
“If you use a calculator to divide: 3/2, 5/3, 8/5, 13/8, etc. you will see that they tend to the decimal fraction: 1.6180339.. . (Note that this number has a unique property shown by 1/1.6180339 = 0.6180339)
“This special number, 1.618.. , is called the golden ratio. It has been used for centuries in architecture for the ratio of the sides of buildings, in art work as the ratio of the sides of a picture; it is the ratio of the height to width of Mona Lisa’s face by Leonardo, and on and on.
“It is an aesthetically pleasing ratio. “ I measured her pretty face, and said it fitted the pattern. She rewarded me with a smile.
As I ponder these designs, I conclude that our Maker is not only Himself astonishing, but He loves for His creatures to enjoy the beauty of the creation. “Let them praise the name of the Lord! For He commanded and they were created.” (Ps. 148:5)
For His eternal power and divine nature have been clearly perceived, ever since the creation of the world, in the things that have been made. (From Romans 1:20)
My 3rd grade grandson is very alert and a deep thinker for his age. We have some good talks and I enjoy swapping ideas with him. We have been talking on our trips to the YMCA and back.
I asked him, “What should I write about this week? How about vacuum chambers?”
He thought for a while. “You were supposed to write about astronomy. How about Black Holes?”
“O.K. Do you know what a black hole is?” I thought we had talked about it a long time ago.
His memory for details amazes me. He said, “It’s a place where the gravity is so strong that not even light can escape.” (I’m not sure of his exact words, and he will correct me, I’m sure.)
I asked him, “Why can’t we see a black hole?” He wasn’t sure, so I told him, “If no light can get out, then there is no light to see it by. Of course, if the whole sky is lit up by galaxies of stars, then we should be able to see a spot where there is an absence of light, and that might be a black hole.”
I continued, “But black holes are so small and so far away, that we have never been able to really see one, as far as I know. But we have seen points in space that are radiating energy from what seems to be from material being sucked into a black hole, never to escape again – at least that is the theory.”
Why can light not escape? It’s because light loses energy as it travels away from a star – it doesn’t lose speed – the speed of light is always the same; however we can see its loss of energy by its wavelength getting greater – its color shifts toward the red end of the spectrum. If the gravity is strong enough, the light loses all of its energy and cannot get out. In fact, it is thought the photons of light actually fall back toward the star.
If no light or any other radiation can escape from the massive star, then it has become a black hole. When stars have burned up all their fuel, the gravitational pull of the star upon itself causes it to collapse into a very dense object which is predicted to become a white dwarf (a star that is white hot, but cooling down to be a brown dwarf). Or it could become a neutron star where protons change into neutrons because the gravity is so strong. Or if the mass is great enough, it could become a black hole.
It is estimated that when a star about 10 times the mass of our sun collapses, it will become a black hole, smaller in diameter than the earth, but with a mass that is about 3 million times that of the earth.
And that concludes our brief description of black holes.
“For His eternal power and divine nature have been clearly perceived, ever since the creation of the world, in the things that have been made.” (From Romans 1:20)
Let all the earth fear the LORD: let all the inhabitants of the world stand in awe of him (Psalm 33:8)
I discussed last time that the speed of light is constant as measured by the observer no matter how fast he himself is moving. For example, if a space ship were moving at a speed of 90,000 miles/sec, toward a star, a beam of light from that star would still measure as having a speed of 186,000 miles/sec, the same as it would measure when the space ship is at rest compared to the star. Classical physics, and common sense, would say that it should measure 186,000 + 90,000 miles/sec, but common sense fails here.
This result, when predicted in 1900 or so by Einstein and Lorentz, did not seem credible, but it has been shown many times to be true with experiments. Even more incredible are the consequences of this: moving clocks slow down (as measured by an observer “at rest”), and moving objects get shorter along the axis of the motion, again as measured by a person at rest. These are called “time dilation” and “space contraction“, respectively.
Why is it called relativity? Let’s imagine 2 identical rocket ships coasting by each other in empty space at a high velocity. Each could say that the other ship was moving and he himself was at rest. There is no detectable way for them to say who is moving. It is all relative.
And the time dilation, etc. is reciprocal. Each space traveler would observe that the other ship’s clock was losing time compared to his own clock and that the other ship was shorter than his own. How can this be?
Welcome to the weird world of relativity, the effects that normally can only be detected by very precise instruments, like atomic clocks, or in the case of objects moving near the speed of light. For example, one early observation was that certain cosmic ray particles (called mesons) created in the earth’s upper atmosphere, with well known, very short life spans, would not be seen as plentifully as they are at the earth’s surface unless their life-spans were extended about 10 times by moving at about 99.5% of light speed.
There is an easy-to-read and entertaining fantasy book written by George Gamow in 1946, called Mr. Tompkins in Wonderland. (An updated version, called Mr. Tompkins in Paperback, is available at bookstores – I just found some used ones on-line for $3). Mr. Tompkins attends a lecture on relativity and then dreams he is in a wonder land where the speed of light is 10 miles/hour. So these effects upon time and length are obvious just by watching ordinary motion. For an example, a bicycle goes by and looks much shorter in length than it should. And as the cyclist speeds up, the length of the bike shrinks even more.
Mr. Tompkins, then gets on a bicycle to catch the other rider. When he gets to moving, he notices that the buildings on the street start getting skinnier and skinnier the faster he moves. And then he realizes why it is called “relativity” – each observer sees things from his relative frame of reference, He notices that the distance to the other biker shrinks, and that the other biker himself looks normal when they are traveling at the same speed. The story is wonderful fiction, yet reflects a reality that we don’t ordinarily see because the speed of light is so great in our universe.
The discovery of the law of relativity has uncovered another mysterious wonder of creation that continues to amaze God’s sons and daughters and causes them to honor and glorify Him.
