Look as the PhD in physics on the forum I have to say that the article is right. The first law is a tautology. It is always true but thats all it tells you, any weight gain or loss has an equal difference in energy entering and leaving the system. But the article is completely correct that there is no causality in that equation. The best analogy is a crowded room, if I asked why the room got more crowded it is completely true that it because more people entered than left.
This analogy is a logical equivalent to CICO. Energy is NOT stuff at all. Concepts do not turn into real objects. And those people are correct. The body can exert involuntary control over body fatness. SROP abusing physics. STOP abusing energy. Energy is NOT itself anything.
That is ALL conservation of energy means. THE body can do things with breathing rate to exert control. STOP misusing conservation laws. Atoms are what add fat tissue.
The entire fitness industry is physkcs illiterate. What you fundamentally fail to understand is that the First Law of Thermodynamics is driver-agnostic. In other words, it does not matter which variable of the system you are controlling. Energy consumed and processed in excess of that which is expended will be stored.
Whether it is stored as fat or as muscle or as other tissue is dependent upon other variables, but suffice it to say, weight will increase because of the mass retained from food in order to create the storage medium.
Energy expended in excess of that which is consumed necessarily leads to the body retrieving stored energy from somewhere. Whether it is retrieved from fat or from muscle or from other tissue is dependent upon other variables, but suffice it to say, weight will decrease because of the storage medium being broken down to recover its stored energy, converted into waste product, and expelled.
Failing either of these, your weight will change. The First Law has every place in human nutrition, but not in a vacuum. Other variables must be considered because the one thing that we do have some control over is how the First Law is applied to human physiology.
Denying the First Law is the first step in making excuses, and you should stop. This guy is an idiot. Energy absorbed, not ingested vs energy burned equals weight loss, homeostasis or weight gain, it cannot be refuted.
You cannot gain weight without a caloric surplus, impossible. Sans water. Facts are that food taken I to the body has a limited number of fates: it gets broken down and used as energy with the metabolites being excreted or it gets added to the body as fat, muscle or other tissues. Sure foods have varying thermogenic effects and doing exercise can lead to foods being laid down as muscle. No amount of harping on about hormones etc can change this.
Eat too much, you get fat. And the laws of thermodynamics very much apply. Press enter to begin your search. No menu assigned! Sharing is caring Nutritionists have been telling us to pump up the fibre Recent Articles. Nice People are addicts too November 1, Leaked internal research shows Instagram knows how much it harms teens and does nothing about it October 3, September 26, Next Post How to spend a fortune on health and achieve nothing aka the Budget Edition.
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If you eat just the right amount of food, then your average internal energy remains constant. The reverse is true if you eat too little.
This process is how dieting produces weight loss. Life is not always this simple, as any dieter knows. The body stores fat or metabolizes it only if energy intake changes for a period of several days. Once you have been on a major diet, the next one is less successful because your body alters the way it responds to low energy intake. Your basal metabolic rate BMR is the rate at which food is converted into heat transfer and work done while the body is at complete rest.
The body adjusts its basal metabolic rate to partially compensate for over-eating or under-eating. The body will decrease the metabolic rate rather than eliminate its own fat to replace lost food intake. You will chill more easily and feel less energetic as a result of the lower metabolic rate, and you will not lose weight as fast as before. Exercise helps to lose weight, because it produces both heat transfer from your body and work, and raises your metabolic rate even when you are at rest.
Weight loss is also aided by the quite low efficiency of the body in converting internal energy to work, so that the loss of internal energy resulting from doing work is much greater than the work done. It should be noted, however, that living systems are not in thermalequilibrium.
The body provides us with an excellent indication that many thermodynamic processes are irreversible. An irreversible process can go in one direction but not the reverse, under a given set of conditions.
For example, although body fat can be converted to do work and produce heat transfer, work done on the body and heat transfer into it cannot be converted to body fat. Otherwise, we could skip lunch by sunning ourselves or by walking down stairs. Another example of an irreversible thermodynamic process is photosynthesis.
This process is the intake of one form of energy—light—by plants and its conversion to chemical potential energy. Both applications of the first law of thermodynamics are illustrated in Figure 4. One great advantage of conservation laws such as the first law of thermodynamics is that they accurately describe the beginning and ending points of complex processes, such as metabolism and photosynthesis, without regard to the complications in between.
Table 1 presents a summary of terms relevant to the first law of thermodynamics. Figure 4. Heat transferred out of the body Q and work done by the body W remove internal energy, while food intake replaces it. Food intake may be considered as work done on the body. Since the body is inefficient, the excess heat produced must be dissipated through sweating, breathing, etc.
Skip to main content. Search for:. The First Law of Thermodynamics Learning Objectives By the end of this section, you will be able to: Define the first law of thermodynamics.
Describe how conservation of energy relates to the first law of thermodynamics. Identify instances of the first law of thermodynamics working in everyday situations, including biological metabolism.
Calculate changes in the internal energy of a system, after accounting for heat transfer and work done. Making Connections: Law of Thermodynamics and Law of Conservation of Energy The first law of thermodynamics is actually the law of conservation of energy stated in a form most useful in thermodynamics.
Making Connections: Macroscopic and Microscopic In thermodynamics, we often use the macroscopic picture when making calculations of how a system behaves, while the atomic and molecular picture gives underlying explanations in terms of averages and distributions.
Example 1. Later, there is heat transfer of What is the net change in internal energy of the system? What is the change in internal energy of a system when a total of See Figure 3. Conceptual Questions Describe the photo of the tea kettle at the beginning of this section in terms of heat transfer, work done, and internal energy. How is heat being transferred? What is the work done and what is doing it? How does the kettle maintain its internal energy? The first law of thermodynamics and the conservation of energy, as discussed in Conservation of Energy , are clearly related.
How do they differ in the types of energy considered? Heat transfer Q and work done W are always energy in transit, whereas internal energy U is energy stored in a system. Give an example of each type of energy, and state specifically how it is either in transit or resides in a system. How do heat transfer and internal energy differ?
In particular, which can be stored as such in a system and which cannot? If you run down some stairs and stop, what happens to your kinetic energy and your initial gravitational potential energy? Give an explanation of how food energy calories can be viewed as molecular potential energy consistent with the atomic and molecular definition of internal energy.
Chemistry Bootcamp Lectures Liquids - Intro A liquid is a nearly incom…. Recommended Videos Problem 2. Problem 3. Problem 4. Problem 5. Problem 6. Problem 7. Problem 8. Problem 9. Problem Video Transcript So in food, you'll often see that on the nutritionist label, you'll see something that looks like the number of calories with an uppercase cease calor freeze. Liquids - Intro A liquid is a nearly incompressible fluid that conforms to the shape of its ….
How is the energy value of foods determined? Why bother to eat? What are the three primary uses for cellular energy? Using chemical terminology, explain the purpose of food refrigeration. Why do we cook starchy foods? To what end product is the energy of foods converted in the catabolic pathwa…. Strictly speaking, why will a refrigerator that contains a fixed amount of f….
Why are fats a good source of energy for storage in the body? What are the two main purposes for the catabolism of the food we eat? How does the addition of salt or sugar help preserve food? Share Question Copy Link. Report Question Typo in question.
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