on my way to the pier on world teacher's day. i was thinking, the water flowing in pasig river has kinetic energy. the law says energy is never created nor destroyed it just transfers or transforms to another form of energy. so what happens to the kinetic energy when the flowing water reaches the sea and stops flowing? science books and science teachers don't teach you this maybe because it's illegal. they only teach stuff we can figure out ourselves like a billiard ball hitting another billiard ball, or flowing water turning a turbine converting kinetic to mechanical to electrical energy. but they don't teach you what happens when there is no turbine and water stops flowing when it reaches the sea. they only give examples of energy transformation, and science books and the internet is littered with so many of this that we can figure our ourselves but it never gives real examples of energy never created or destroyed. they give examples of chemical energy in your body cells converted to kinetc energy when you push the grocery cart. but they don't tell you what happens to the energy when it hits a shelf and comes to a complete stop. maybe because they are afraid of going to jail. or an example of a chemical potential energy in a dynamite converting to heat and sound energy when it explodes. but the sound does not go on forever and at some point there is no more heat. so what happened to the energy? did it get destroyed? my guess is that maybe when the grocery cart hit the shelf the collision caused heat energy, although too little for senses to detect or observe. same with sound energy maybe it converts to heat because i can't think of any other possible outcome. the heat energy produced from the grocery cart and shelf collision will just merge or join the heat energy that already exists in our atmosphere. heat always travels from hot to cold so at night heat in our atmosphere will escape to space and travel forever and ever and ever in space in radiation wave form until it hits another heavenly object and the cycle continues. i said "at night" because during the day the incoming rays of the sun is heating that area between our atmosphere and space. THAT'S AN EXAMPLE OF ENERGY NEVER BEING DESTROYED !!! whew !!! i'm the first in history of mankind to ever give an example of energy never destoryed. i challenge you to search all over the internet for this.
now let me give you an example of energy never created - heat in our atmosphere comes from the sun. the sun comes from the big bang. where does the big bang come from? nobody really knows in the first place big bang is just a theory and my favorite tv sitcom. and that's ok. i'm not asking for much. but again, i'm the first one in history of mankind to give an example of energy never created.
so looks like heat energy is the celebrity of all forms of energy so i did more research and it's actually fascinating if only the science books explains heat energy the way i'm about to explain it in this blog.
science books and science teachers don't tell you that heat energy is not a substance or particle. all my life i thought it was a particle like the photons in light or the waves in electromagnetic spectrum. the photons and waves do contain energy but they are not energy. you might ask, is energy an invicible force like the gravitational force? not even. gravitational force contains potential energy but it is not energy. gravity or electromagnetic force is something you feel like a push or pull, while energy is just an abstract concept. it's just a measure of the ability to do work. gravity has energy because when you jump off a cliff it has the "ability" to pull you down and break your bones when you hit the ground. it's like a property of something similar to how high a person can jump. how high a person can jump is not a substance, a particle or a force. it's an ability. heat is really just the amount of work a matter can do because of the movement or VIBRATION of it's molecules. example of that work is turning the turbines in a steam engine. the phrase "movement of molecules" is confusing because the student might think the molecules are traveling from one place to another when it's really just staying in the same place but vibrating.
even ice contains heat. sounds ridiculous? that's because even the molecules in ice are still moving, just much more slowly compared to boiling water. ice can still do work - it can even boil to evaporation certain liquids like freon (at atmospheric pressure), whose boiling point temperature is much lower than the freezing point of water.
notice what i just said in the previous paragraph. that's actually bad teaching because i just threw at you the words like boiling, evaporation, and pressure as if it's something you really understand based on your observation on evaporating water and boiling water. this is why many students hate science. sure they can brute force memorize the scientific laws and formulas and processes and get perfect scores in the exams even if they really have no clue what really is going on.
first, let me throw you some knowledge bombs to stimulate your interest - aircons cool the air by boiling something (freon). sounds ridiculous? isn't boiling something means you are heating something?
now that i got your attention, let me first explain that heat energy always travels from hot to cold. cold is just the absence or lack of heat. aircons are not giving cold air - it's absorbing or transfering heat from hot air around it into or towards the inside of the aircon system to cool that air and blow that cooled air around the house to cool the air in the house. but didn't i just say energy is never destroyed? what happens to the heat energy that the aircon system absorbed? well it has to spit it out or at some point the aircon system won't work anymore, meaning it cannot absorb any more heat because heat travels from hot to cold and if the amount of heat inside the entire aircon system is hotter or the same temperature as the air around the house, then it cannot absorb the heat in the house anymore. it has to spit out the heat through that grill (condenser) outside of the house that's why you feel hot hair coming out of the condenser outside the house. but wait, doesn't heat travel from hot to cold? but that thing or substance inside the system that just absorbed the heat from inside the house is still much colder than the air outside the house? how can you spit out the heat outside the house when heat only travels from hot to cold? that's where the compressor in the aircon system comes in. it compresses that substance (freon) gas to heat it up. when you compress gas, the pressure increases so the molecules vibrate faster. heat energy increases as the molecules vibrate faster. liquid cannot be heated by compressing. luckily by the time it reaches the compressor, freon is already in gas form. why is it in gas form? because freon has a very low boiling point - much lower than the air inside the house (even when it's already cold). that means the air inside the house is actually heating up the freon inside the aircon system just like what fire in your stove does when it heats the water in the pot. just like water boils and evaporates at some point, the liquid freon the aircon will boil and evaporate (but still trapped inside the closed aircon system) and be pushed towards the compressor. it's actually hitting 2 birds with 1 stone because evaporation is when the transfer of heat is fastest so the cooling of the house is more efficient.
so now that the compressed freon gas is hotter than the air outside the house, heat can now transfer from inside the aircon system (condenser) to the air outside the house. when you remove heat from any gas, it condenses to liquid. so now you have very hot highly pressurized liquid travelling towards the evaporator inside the house. but wait. now we have another big problem. didn't i say heat only travels from hot to cold? how can heat inside the house transfer into the aircon system (evaporator) if the liquid freon is blazing hot (meaning the molecules are vibrating super fast)? how do you cool it so it will be colder compared to the air inside the house? answer: you lower the pressure. the lower the pressure, the slower the molecules vibrate so the substance becomes colder. how do you lower the pressure? simply constrict the pipe or allow only a small opening to enter the evaporator. example if you poke a small hole on a highly pressurized water pipe and redirect the water coming out of that small hole into a secondary pipe much larger than the small hole, the water pressure inside the secondary pipe would be much lower. except unlike water, freon's natural behavior is that the molecules immediately vibrate very slowly at a certain low pressure, making it much colder than the air outside the house. so now heat from the air inside the house can now transfer inside the aircon system (evaporator) and the cycle repeats.
in fact if you make the pressure too low or the same as atmospheric pressure (0 psi) the freon will be too cold to the point that the transfer of heat from inside the house into the aircon system would be too fast. but isn't that what we want? won't the thermostat just turn off the compressor if the house is already cold enough? what's the problem? the problem is that if the transfer of heat from the house to the evaporator is too fast, air around the evaporator will ice up and choke the aircon system. meaning the spaces between the grills of the evaporator will be blocked by the ice so there will be no more airflow. so even if your evaporator is now a freezing block of ice, it would still be hot inside your house because that coldness cannot be blown around the house by the blower anymore. that is why the opening into the evaporator should still be large enough to maintain a certain pressure (~70psi for r22 freon). at 70psi, r22 freon evaporates at 40 degrees farenheight (40F), which means if the temprature in the house is let's say 75F, it will still be hot enough to boil the r22 freon inside the evaporator meaning there would still be heat transfer from the air inside the house into the aircon system, thus cooling the air inside the house. it just won't be able to cool the house below 40F, but who wants to live in a house that is 40F? the comfortable temparature for human body is usually 68F to 72F.
again, i want to apologize for using the term "heat transfer" before i even taught you what heat transfer really is. i already said heat is the ability to do work because of the vibration of molecules. note that heat is not the vibration of molecules. HEAT IS NOT EVEN WHAT IS CAUSING THE MOLECULES TO vibrate. what is causing the molecules to vibrate? as far as i know, there are 2 things that is causing the molecules to vibrate:
1) GOD. or in more scientifict terms, it's just the property of the matter created since the big bang or the creation (from a religious perspective). it's like asking why electrons move around a nucleus. it's just the nature of the object or matter that cannot be explained further . or it's a knowledge you just have to accept without explanation.
2) CO- INFECTION OR CO-INFLUENCE from the surrounding molecules that are moving faster .science books are confusing because they say "heat transfer" or "adding heat" as if something is being transfered or added when in reality, nothing is being transfered or added. there is just an infection or influence. i'm also guilty as charged when i kept saying heat travels from hot to cold, when in reality, nothing is really traveling - it's more like the behavior or faster vibrating molecules is co-infecting or co-influencing the slower vibrating molecules around it to vibrate faster. i added the prefix "co-" because it's a 2 way influencing. think of molecules as racist people who don't want diversity. they want to be the same. except the faster vibrating regions of molecules will also slow down. so it's like a white racist person influencing a black person next to him to turn brown, but the white person also turns brown so they have the same color. so molecules are more like "compromising racist people".
instead of heat transfer, it's best to say "EQUILIBRIUMIZATION OF THE VIBRATING SPEED OF NEIGHBORING MOLECULES". i know "equlibriumization is not a word but it's more effective. don't try to be correct. try to be effective. example, obama always tries to be correct so if during yolanda obama was to warn tacloban city about the incoming storm surge, he would have shouten "there is a storm surge coming !!! there is a storm surge coming !!!". people at that time don't have a clue what is a storm surge so they look up in the sky and prepare for heavy winds. what obama said was very correct but everyone in the city dies. if that was donald trump he would have shouten "there is a tsunami coming !!! there is a tsunami coming !!!", which is very incorrect but people would have run for the hills and their lives would have been saved. then after the storm CNN will condemn trump for his technically incorrect statement and interview americans who would say they are ashamed to be an american because the american president don't even know the difference between a storm surge and a tsunami.
so in summary,
- heat should be defined as the vibration of molecules.
- heat energy should be defined as the ability of a matter to do work as a result of it's vibrating molecules.
- heat transfer should be defined as the co-influencing of the speed of vibration of neighboring molecules so that their vibration speed will be the same.
now you tell me if there is a science book that would teach heat energy the way i just taught it :-) however i'm not really sure if the things i'm saying here are correct.
(for more of my knowledge bombs, click the "ian's knowledge bombs" banner at the top of this article and choose any article in the table of contents that piques your interest)
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