Forces of Air Pressure

During my tenure as an earth science teacher weather was one of my favorite units of study. I hoped it would become a student favorite as well. Many of the experiments we assembled to teach weather concepts possessed an element of the “wow factor.” My reticence about over-stressing the pure entertainment value of science demonstrations took a back seat as we realized that learning real world scientific facts could be wholly instructional and entertaining at the same time. Air pressure demonstrations fell into the dual category of instruction plus entertainment.

Pedagogically, science instructors could argue that learning book facts should not precede a classroom demonstration. This depends on the nature of the facts being learned. If facts concerning the existence and action of air molecules are not readily apparent, the teacher may initially discuss the existence of billions of invisible air molecules randomly zig-zagging through the air striking neighboring molecules and surfaces in the environment. Their movement is due to the heat energy present in any sample of matter above the temperature of absolute zero. Molecules always possess kinetic energy—the energy of motion. Collectively, impacts of billions of whirling molecules against surfaces result in the constant force of air pressure. Ordinarily we do not perceive these considerable forces, but classroom demonstrations enable the teacher to affirm their existence.

As a prelude to lessons concerning air pressure it may be appropriate to promote wonder in students about the beauty of our air blanket. Air is low in density but its attraction by earth’s gravity is necessary for life on earth and makes air pressure phenomena possible. It is a protective layer against harmful radiation from outer space such as ultraviolet. The atmosphere helps warm the earth and protects planetary life from extreme heat or cold. The 21% oxygen level is life-giving for animals. The trace amount of CO2 is life-giving for plants. Oxygen permits combustion of fuels. Our world would be without sound except for the presence of our atmosphere. Circulation of air distributes life-sustaining precipitation. Mastery of facts about our atmosphere is a life long project for professional atmospheric scientists. The air pressure topic is of vital significance in atmospheric science. 

Each cubic meter of atmosphere contains 7.5 septillion molecules of mostly nitrogen and oxygen. The pressure results in a substantial force of 14.7 lb. per square inch. This is illustrated by a 14.7 lb. weight pressing down on an area of one square inch. The average man’s body has about 2500 square inches of surface area. This calculates to roughly 18 tons of total pressure. Man does not feel this enormous pressure because his body’s internal pressure pushes back with equal force. The forces are usually balanced so he does not feel pressure from any direction. Only if internal pressure were reduced or increased or if external pressure were reduced or increased would our subject feel any effects. Ordinarily such pressure changes do not occur.

We begin with of one of the most spectacular demonstrations of the force of air pressure. This demonstration had a strong visual impact. We needed old-fashioned two gallon rectangular methanol or motor oil cans for our “wow factor” experiment, making sure no volatile vapors were left in the can.

The can with a small amount of water was heated with a propane burner until the water boiled long enough for steam to escape from the open can for at least a minute. After extinguishing the torch we tightly capped the can. I told the students to be quiet, watch, and listen. After a little while the can began to make noises as the can crinkled and collapsed before our eyes. The invisible force of air pressure was collapsing the can before our eyes—the same force that presses on our bodies every moment. (The can had been filled with water vapor after boiling the water. It began to condense back to a small amount of liquid water leaving a vacuum in the closed can. The force pushing out was no longer equal to the external force pushing in. Strength of the can was no match for strength of the outside air pressure.) The strongest boys in the classroom admitted they might be unable to match the destructive force of air pressure!

The behavior of molecules in air is tantamount to mayhem. They speed around chaotically, colliding with other molecules or with surrounding surfaces multiple times per second at a speed of about 1000 mph. On the scale of molecular sizes the distance between molecules is very great. Over 99.9% of air in our room is empty space. But trillions of tiny particles colliding with our bodies and with our demonstration can uncounted times per second at 1000 mph produced a startling visible and audible effect. The behavior of any one air molecule unpredictably moving about with kinetic energy is impossible to describe. In contrast, the collective behavior of gas molecules in our atmosphere may be accurately described by numerous gas laws.

Was the collapsed can experiment an example of magic? Or did it fuel our desire to explain phenomena with scientific inquiry? What is the basis of the “wow factor?” Laws of science, including the laws governing the behavior of air, were established by the Creator who initiated time, space, matter, and energy in the beginning. The Creator allows us to discover these laws and to describe their effects on humanity. 

      

  

   

       

  

Into Thin Air

The popular idiom “Vanish into thin air” has acquired meaning in our modern experience. It refers to a mysterious disappearance of something which is no longer visible but may still be present and real. Not always does the expression apply to a literal physical substance. It could indicate, for example, the peculiar disappearance of funds from a bank account or the loss of a large lead in a game of basketball. In the sphere of science there are some examples of visual vanishing such as the  evaporation of water or sublimation of ice or snow. Visible clouds may vanish as condensed micro-droplets of clouds re-evaporate into the air. 

How thin is air, we might ask? Compared with most solids and liquids in our daily experience, we answer, “Very thin.” But not until we begin studying and experimenting do we realize that air may not be all that thin. The layer of air which envelops the earth is almost all within ten miles of earth’s surface. In relation to the distances we travel to our local supermarket, the layer of air surrounding our planet is actually rather “thick.” Air fails to meet another common definition of thin: “Having few parts or components in relation to a given area.” In terms of “parts” in relation to a given volume such as one cubic meter, air has 2.5 septillion parts (molecules). We cannot see air molecules so how do we know they exist? Is there any way we may perceive the effects of these invisible molecules—2.5 septillion of them in only one cubic meter?

Let’s answer a few other questions about our proverbial “thin” air. One cubic meter of air has a mass of 1.3 kg—about 2.9 lb. In our home’s small office which also serves as a library and computer room, the 53 cubic meters of thin air has a mass of about 150 lb. This air surrounds us from every direction—top, bottom, and from every side angle of our bodies. The invisible, real, thin air which surrounds us has a number of powerful, sustaining effects on our lives.

Air is invisible matter. On our planet most matter is visible. Air, along with other types of visible matter, has mass and takes up space. Another invisible factor in our environment is energy. Energy is not matter, but it also has strong effects on our lives. Energy is the capacity to do work. This simple definition does not tell us very much about energy, its forms, or the quality and quantity of its effects. For now we will let the definition stand on its own. Other invisible factors in our environment relate to the phenomena of mind and spirit. Power of mind and spirit is not matter-based. God is Spirit (John 4:24). His existence is elevated above our matter-based existence. The power of our human mind helps us access the concept of God as Spirit. As humans we share awareness of the element of mystery concerning the reality of both mind and spirit.

Returning to the thin air surrounding us invisibly, we continue with a brief introduction to “air pressure.” Molecules of air—2.5 septillion of them in a single cubic meter—are continually zig-zagging around with kinetic (motion) energy. Our bodies and everything in our environment are being bombarded by constantly moving air molecules. The force of this bombardment is called “air pressure.” In our upcoming posts we will deal with some fascinating phenomena of air pressure, the invisible force on our bodies exerted by the impacts of billions of moving air molecules surrounding us.

A scripture verse comes to mind relating to moving air—wind: “The wind blows wherever it pleases. You hear its sound, but you cannot tell where it comes from or where it is going. So it is with everyone born of the Spirit” (John 3:8 NIV). Air moves because of differences in air pressure from place to place. But even if there is no pressure differential capable of producing breezes or stronger winds, the pressure exerted by trillions of impacts of moving air molecules provides dozens of fascinating, impactful phenomena sustaining our everyday life.

We conclude with a family incident involving the concept of “invisible, but real.” During the Easter visit from our children and grandchildren, the conversation turned to many “invisible but real” experiences of our lives. Several days later our 3 1/2 year old grandson noticed an unusual event while taking his daily bath. His mother texted us with the ensuing conversation: “I made up another invisibility reality—air molecules! In the bathtub he put a cup upside down and I noticed that it didn’t fill with water. We talked about why, and the invisible reality of air. Then (our grandson) mentioned that God is real even though we can’t see him. Such a fun science lesson…that points to our Creator.”

The forces of constantly moving air molecules pressing back against the water from the inside of my grandson’s bath cup kept the water out of the upside down container. It balanced the force of outside air molecules pressing the water inward. Had no air been inside the cup at the beginning of the “cup experiment” the water would have immediately filled the cup. Instead, the considerable force of thin air inside the cup opposed the considerable force of the thin air outside the cup. The forces were balanced when the appropriate water level was reached.

We disclaim that our references to the invisible but real qualities of God or the many analogies of invisible but real phenomena in our experience is conclusive proof for the existence of God. The New Testament book of Hebrews offers a well argued case for the certainty of “what we do not see,” however. Taken together passages from this epistle offer thoughtful support for our theistic belief system. “By faith we understand that the universe was formed at God’s command, so that what is seen was not made out of what was visible” (Heb. 11:3 NIV). The worldview of naturalistic, atheistic materialism becomes increasingly difficult to defend as we observe the wonders of our environment—both the visible and the invisible.      

   

     

   

Visions of God

In a metaphorical sense we may have heard the term “seeing God.” Recently I have encountered several parents who have been challenged by questions from their children concerning the reality of God’s existence. Adults are also challenged by questions from their friends concerning the reality of God. This is a hot discussion topic—one which deserves more attention from our adult church discussion forums. Adults may understand the figurative expression “seeing” God differently than children. Levels of understanding for children and adults could and should be considerably different.

Historically the Israelites experienced powerful manifestations of the presence of God during their desert wanderings prior to entering the promised land. These startling encounters at Mt. Sinai are documented in the Book of Exodus. Moses ascended the mountain at least eight times. God spoke audibly to Moses on the mountain concerning past and upcoming events. The people were instructed to prepare to meet God. The meetings were awesome, frightful occasions featuring fear-provoking episodes with lightning, thunder, smoke, trumpet blasts, and trembling of the mountain.

The reality of God as expressed in the Exodus chronicle at Mt. Sinai may not be a lesson for an ordinary Sunday School class of primary school students. This illustrates the importance of “age-appropriate” teaching, but not because the traits of God are off-limits for study. Deep study reveals that God does not limit himself to our dimensionality of length, width, height, and time even though he fashioned these dimensions when he created “the heavens and the earth,” an expression encompassing “all that exists.” God also created matter, energy, and the four fundamental forces of the universe which act among the particles of matter. Our Creator, therefore, is far superior to his creation. 

One way God is superior to his creation is that he created more than the familiar dimensions in which we ordinarily exist. Many physicists pose the fascinating scenario of the existence of invisible, extra dimensions of space—perhaps 10 or 11 dimensions altogether. Our ordinary lives exist in only one time dimension going from the past, to the present, to the future. Some physicists believe there could be other dimensions of time beyond the forward moving dimension governing our lives. The omnipotence of God who created all things may be more easily grasped if we recognize the reality of dimensions unfamiliar to us in our daily lives. God created other dimensions. He exists in unfamiliar dimensions, but could confine himself to our dimensions when he wishes. Jesus Christ, the Son of God, confined himself to our dimensions in order to communicate his message of care and love for humanity. 

The post-resurrection appearances of Jesus would not be possible unless he existed in extra dimensions. He entered rooms “the doors being shut,” ascended to the Father, and returned bodily. The disciples were living in ordinary dimensionality, but Christ’s resurrection body was not ordinary. Christ could still operate in our dimensions in order to eat breakfast with the disciples and permit Thomas to feel the nail prints in his hands and the wounds in his side. A remarkable passage in the Mt. Sinai chronicle occurs in Exodus. Four leaders including Moses, along with seventy elders of Israel “…went up and saw the God of Israel. Under his feet was something like a pavement made of sapphire, clear as the sky itself. But God did not raise his hand against these leaders of the Israelites; they saw God, and they ate and drank” (Exodus 24:9-11 (NIV).

In other Exodus passages the people were cautioned not to approach the mountain under pain of death. In what one writer described as a “very heavy text,” the lesson to be learned is that the people were subjected to fear, awe, and reverence of God so they wouldn’t treat God casually. They were to be tested and proven. In the eons prior to the Mt. Sinai law-giving, human conscience proved to be completely inadequate to bring about righteousness in humanity. The Mosaic law illustrated the necessity of man to obey a higher authority than himself; specifically, the higher authority was God, the Creator.

In several passages where the written language of the Bible uses the term “see God” we pose the likelihood that a person saw a vision of God’s glory without actually seeing God’s face. Moses himself, late in the law-giving process requested of God, “Now show me your glory.” God placed Moses on a rock and said, “When my glory passes by, I will put you in a cleft in the rock and cover you with my hand until I have passed by. Then I will remove my hand and you will see my back; but my face must not be seen” Exodus 33:18-23. One commentator offered the possibility that men could probably see some outward sign of his presence such as a bright cloud or great blaze of light. These are mysterious and wonderful events beyond our complete understanding.

In our day it is imperative to review with our children the fact that we do not see God visually but we note numerous manifestations of invisible forces, abundant design features, and the predictable orderliness of the natural world. In particular, the physical features of living things and the remarkable developmental regeneration of plants and animals is apparent all around us. Our scientific knowledge gives us more profound knowledge of our powerful Creator than the Israelites under Moses ever experienced. Parents, youth leaders, and pastors must actively search for opportunities to produce a mature vision of God.    

  

            

       

Faith in God's Reality

Many of our recent posts have been written with children in mind. How successful are parents in presenting God as real for our children? How could Sunday School teachers do the same for their students to affirm that God is real? We may also ask how our pastors could present biblical theology from their pulpits in a convincing manner. Theology is defined as the science of God. In a word, the root meaning of science is knowledge—including the fundamental knowledge that God is real. This knowledge is for both young people and adults.

For our high school and college age young people, we trust that knowledge of the reality of God’s existence has been established with reasonable certainty. For our adult population we likewise assume the reasonable certainty that the “God reality” has been established. If there are serious doubts about that reality, the validity of the fundamental message of our churches may be called into question.

Primary school students and much younger children may present a blend of least and at the same time, most challenging assignments for parents and teachers with respect to the question of God’s reality. Teaching about the reality of Jesus, God’s Son, may be a simpler responsibility. Children are visually oriented from the beginning of their life. In that sense, the challenge of teaching about an invisible God could be substantial for some children.

One primary task of parental teaching is instructing children that real things are not always visible. Yet, these real, invisible things have effects which may be seen and felt. We caution that the mere awareness of invisible forces, even the forces which have an effect on surrounding matter, may not prove to doubters that God is present or even that he exists. God, of course, is the author of “sustaining miracles” whereby the universe is sustained from moment to moment by God’s will and power. If God’s will and power were to be withdrawn, the universe would descend into chaos—a difficult concept for children. The orderliness of the natural world manifest in dozens of physical constants is strong affirmation of God who authors sustaining miracles.

We challenge parents, teachers, and pastors to think deeply about the issues of fostering and strengthening faith in the reality of God. Ultimately each person must embrace faith in God as a matter of personal choice. These are matters of eternal import. We are privileged to help mold the world views of our children and fellow man.

The writer of the Book of Hebrews presented numerous examples of the outworking of faith in Christian believers. “By faith we understand that the worlds were prepared by the word of God, so that what is seen was not made out of things which are visible” Heb. 11:3 (NAS).    

   

Invisible God-connection

In our desire to make the existence of God real for our children we may also consider how vital it is to make God real for ourselves and our adult friends. The author of the fourth gospel and the epistles of John made clear statements: “No one has ever seen God” (John 1:18; I John 4:12). There is no exception, except in the experience of Jesus Christ himself. The God of Judeo-Christian Scripture is an invisible Deity who made His voice audible on several occasions in both Old and New Testament times. Our omnipotent, omniscient, omnipresent God, however, cannot be visually seen. The Creator of all things cloaks Himself in invisibility. 

Modern humanity highly depends on visual imagery. God’s invisibility is testimony to the truth that God’s reality exists on a loftier plane. We must investigate the dimensions of that plane. Jesus Christ is the only One who has seen the Father. John records the words of Jesus, the second person of the Trinity: “…not that anyone has seen the Father except he who is from God: he has seen the Father.” Jesus Christ identifies himself as “He who is from God.” 

The writer of Hebrews states the Old Testament sacrifices and offerings are not as desirable as the physical body of Christ offered as a sacrifice for the sins of man: As the second person of the Trinity, Christ proclaimed, “Sacrifices and offerings you have not desired, but a body have you prepared for me (Hebrews 10:5 ESV). Scriptural Divinity is not always invisible, therefore! God the Father is always invisible but Christ the Son became physically visible. Our children may begin to understand the theological depth that God became man in the person of Christ in order to redeem humanity. For many young children, this may be the limit of their comprehension of God until they become older.

As we investigate the importance of God’s invisibility, let us consider the restricted conception of reality if we focus primarily on the importance of visual reality. People could offer God’s invisibility as an excuse to disbelieve in His existence. The humorous cliché “seeing is believing” does not imply its converse. If we understand the physical basis of light and human vision we may grasp the concomitant scientific truth that the energy information transported by the electromagnetic spectrum perceived by the eye consists of only a minuscule fraction of electromagnetic reality. Visible light consists of far less than 1% of the electromagnetic spectrum. Many other types of electromagnetic energy testify to the wonders of the invisible universe. Scientists sometimes use the catch-phrase “Absence of evidence is not evidence of absence” to inspire a lively search for new scientific evidence.

We recall personal experiences with our grandchildren concerning invisible forces. The examples exemplify two of the four fundamental forces of the universe—gravity and electromagnetism. When our grandchildren visited frequently during their pre-school years, our driveway provided the challenge of sprinting or riding down a curving, sloped hill aided mightily by the force of gravity. Grandpa suppressed his fear that the youngsters would seriously injure themselves, tumbling headlong—notwithstanding our warning to, “Watch out, gravity will get you!” Perhaps the children did not fully understand the invisible force of gravity which pulled them relentlessly down the hill, or even the “pull” which quickly returned them to earth after their vertical jumps. Gravity’s invisible force aided in one case and impeded in another.

A small world globe, powered by magnetism, levitates on my office desk. The grandchildren have become aware of the forces holding the globe suspended in air. Magnetic forces may be beyond the reach of early childhood explanation as are the attractive and repulsive forces affecting the small magnetic disc sets we use to post grandchildren’s art on our refrigerator. But they are not beyond the reach of childhood wonder.

A hand-held radio is capable of receiving several dozen local stations by turning a tuning dial slightly to receive different invisible electromagnetic frequencies. The receiver converts the signals to audible sound, also invisible. In our great-grandparents’ youthful days such phenomena would be hailed as “miraculous.” In the 21st century our grandchildren may be inured to the wonders of the invisible. Technological wonders accessed by rapid deployment of finger and thumb-taps may have caused us to lose awareness of the Creator of the coherent physical laws by which the latest modern devices function. Our children might substitute a form of “worship” of modern devices for genuine worship of the Author and Creator of all things. At worst, the dire warning of Romans 1:25 may be considered: Historically, many people “worshiped and served created things rather than the Creator.” Helping our children understand the reality of God is a challenging and awesome privilege.

The above incidents provide examples of the reality the invisible forces. Scientists investigate further in order to understand the causes, effects, and significance of invisible forces on our lives. No one could deny the reality of gravity or the many manifestations of electromagnetism. Science enables us to discover causes and effects of those forces but in no sense do they provide proof for the existence of God. Rather they are analogies suggesting the need for additional investigation. We are connected to the invisible God because we are created In His Image. As God’s children we manifest some of the traits (the effects) of being in His image (the cause). Deeper questions about the reality of God as a Spirit may remain unanswered until our young children are older. References to our Father in Heaven, however, are always appropriate.     

One worshipful traditional hymn by Walter Chalmers Smith (1824-1908), “Immortal, Invisible, God Only Wise,” expresses the depth of beauty and mystery in our understanding of the invisible God. The hymn was inspired by I Tim. 1:17: “Now to the King eternal, immortal, invisible, the only God, be glory and honor for ever and ever. Amen” (ESV). It is a moving, traditional Welsh hymn-tune with potential for deep reflection by worshipers. The Verse 1 text: Immortal, invisible, God only wise, In light inaccessible hid from our eyes. Most blessed, most glorious, the Ancient of Days, Almighty, victorious—Thy great name we praise.” 

    

            

   

God's Invisibility

Theologically, the Biblical revelation that “God is a Spirit” (KJV) is an extremely deep concept. Likewise, the subject of God’s invisibility is exceedingly profound. We cannot see a spirit. Our Christian faith is anchored to belief in the reality of a God who cannot be seen. Humans are accustomed to visual imagery to reinforce reality. If our everyday proposals do not have the advantage of a visual connection, or at least an auditory connection, beliefs in our accounts of reality are often diminished.

As parents or grandparents, we desire that our children grow up to believe in the reality of God. Our own adult belief in the God of Judeo-Christian scripture needs affirmation. Faith, defined as a “life-encompassing belief system” based on “complete confidence and trust” needs links to reality. Even more, we must determine how to present God as a real, living entity to whom we owe our thanks, worship, and allegiance. We understand that conveying the concept of a real God to our children is primary.

How may we explain to children that God is a spirit? Beyond the description of God as a spirit, Scripture instructs us how we should worship Him. The NIV translation presents the most familiar instruction for both the essence of God and how we should worship Him: “For God is spirit, and his worshipers must worship in spirit and truth” (John 4:24). Ken Taylor’s The Living Bible paraphrase goes beyond, saying, “For God is spirit, and we must have his help to worship as we should.” Eugene Peterson goes even further: “God is sheer being itself - Spirit. Those who worship him must do so out of their very being, their spirits, their true selves, in adoration.”

The remainder of our discussion is mostly beyond the scope of children’s  comprehension, but not beyond the reach of adult contemplation. Perhaps as we gain insight into the significance of God as a spirit, we will be better able to answer questions from our children. They sometimes surprise us with insight beyond their years.

The linkage of two terms seems appropriate. Recently we submitted several posts on “consciousness.” We stated that many secular experts feel that the subject of consciousness is beyond the reach of science to explain—a startling admission from scientists who search for naturalistic explanations for virtually every phenomenon. Another term secular scientists are loathe to explain is the existence of “spirit” as used to explain the essence of God as a non-material entity. We link our recent post on the subject of consciousness: 

https://jasscience.blogspot.com/2017/02/consciousness-fundamental-property.html

In the above post we used the term “entity” to aid us in understanding God as the “ultimate supernatural entity of consciousness.” This is not a term used in Scripture, but in terms of our current understanding of consciousness and spirit, we may connect the terms. In human terms, consciousness means “self awareness of one’s existence, one’s thoughts, one’s surroundings.” In supernatural terms, the “consciousness” of God, the Creator of all things, is exponentially and infinitely greater than the consciousness of humans. In describing God as a spirit, we must use adjectives beginning with the prefix “omni:” God is omnipotent—all powerful, omniscient—all knowing, and omnipresent—all-present, or present everywhere.

Some secular scientists consider consciousness a “fundamental building block of nature” in the same league as space, time, matter, and energy. If we describe God as an omnipotent, omniscient, and omnipresent spirit, we might reverently refer to God as a “fundamental building block of the entire universe.” We have been taught the theological truth that humanity is created in the image of God. Author Kenneth Samples refers to the “enigma of humanity” as a direct result of our possession of the image of God with which we were created. Samples also writes that the image of God in humans results in “rational capacities, moral volition, relational distinctiveness, unique spiritual qualities, and dominion over nature.”

Returning to discussion of the responsibility of teaching our children about the reality of God: We discuss the topic of God, praying before mealtimes, bedtimes, and various other times to the invisible God—the ultimate spirit Being and the Creator of everything. Parents must decide concerning the child’s readiness to discuss such important issues. We trust that Christian parents will devote time preparing for these important adult/child discussions. They must study issues for themselves as a precursor to launching ongoing discussion topics with their children.

In our recent post on “Youth Science/Faith Apologetics” (3-13-2017) we wondered what the ancient Israelite parents talked about with their children if they followed Moses’ advice to “…impress them (the commandments) on your children” when they were sitting at home, walking along the road, lying down, and getting up (Deuteronomy 6 and 11). Moses had heard God’s voice on Mt. Sinai even if he did not actually see Him. The events on the mountain had a monumental impact on the Israelite leader. We speculated in our recent post that lessons from the created natural world may have intensified the Israelites’ desire to serve the Creator as well as following His commandments. 

In the 21st century parents who prepare for the discussion about the reality of the invisible God may have an advantage. In addition to our expanded knowledge of the natural world and its wonders of design and order, we have modern awareness of the “hard problem of consciousness” as a reality which far exceeds material reality. Today’s secular scientists such as David Chalmers calls non-material consciousness “the most mysterious phenomenon in the universe.” Chalmers touts an invisible reality of non-material consciousness. Scripture, however, describes the reality of God, the first person of the Trinity, as an invisible non-material spirit on a far higher plane of reality. He is omnipotent, omniscient, and omnipresent—the ultimate, fundamental subject of John 4:24: “For God is spirit….”