Why doesn't gravity violate LoCE?

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In summary, the conversation discusses the concept of the Law of Conservation of Energy and how it relates to the idea of energy appearing out of nowhere. It is explained that the law states that energy must remain constant in a situation, and any changes in energy can be attributed to interactions. The speaker also discusses the concept of gravitational energy and how it can be used to explain the conservation of energy.
  • #1
Crazy Tosser
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Why doesn't it violate Law of Conservation of Energy?
Isn't it energy that comes out of nowhere?
 
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  • #2
Crazy Tosser said:
Why doesn't it violate Law of Conservation of Energy?
Isn't it energy that comes out of nowhere?

How so?
 
  • #3
Gravity manifests as a force, not an energy. Ie, a book sitting on a table experiences a constant force from gravity (and the table), but no energy is being expended.
 
  • #4
It comes from potential energy.
 
  • #5
Crazy Tosser said:
Why doesn't it violate Law of Conservation of Energy?
Isn't it energy that comes out of nowhere?

You should understand exactly what the law of conservation of energy tells us. It tells us that *if we have a certain situation* and we calculate a quantity, called energy, for that situation, and then the situation evolves, and somewhat later, and we calculate the same quantity again, we find the same number.

If the interactions that make the situation evolve from the first to the second state are such that we do indeed find the same number, we say that those interactions "conserve energy".
 
  • #6
Crazy Tosser said:
Why doesn't it violate Law of Conservation of Energy?
Isn't it energy that comes out of nowhere?
It can be shown that if you move an object from a position A to B, then the work done by gravity will be independent of the path: it depends only on the points A and B. So we can define gravitational energy in general point B as work done by gravity when the object moves from A to B (we can chose any A, this just affect a constant in the energy). Consequently energy will be conserved once we add gravitational energy.
 

1. Why does gravity follow the Law of Conservation of Energy?

Gravity is a fundamental force that is governed by the laws of physics, including the Law of Conservation of Energy (LoCE). This law states that energy cannot be created or destroyed, only transferred or converted into different forms. Gravity does not violate this law because it is a conservative force, which means that the total energy of a system remains constant. In other words, the energy of an object affected by gravity may change as it moves, but the total energy within the system remains the same.

2. How does gravity obey the Law of Conservation of Energy?

Gravity obeys the Law of Conservation of Energy because it is a conservative force. This means that the total energy within a system remains constant, even as the energy of individual objects may change. For example, when an object falls towards the Earth, its potential energy decreases while its kinetic energy increases. However, the total energy of the object and the Earth remains the same, demonstrating the conservation of energy.

3. Can gravity create or destroy energy?

No, gravity cannot create or destroy energy. As a conservative force, gravity follows the Law of Conservation of Energy, which states that energy cannot be created or destroyed. Instead, gravity can only transfer or convert energy from one form to another. For example, when an object falls towards the Earth, its potential energy is converted into kinetic energy, but the total energy remains the same.

4. How does gravity affect the total energy of a system?

Gravity affects the total energy of a system by transferring or converting energy between different forms. For example, when an object falls towards the Earth, its potential energy is converted into kinetic energy, but the total energy of the system remains the same. Gravity can also transfer energy from one object to another, such as when the Moon's gravity causes tides on Earth. However, the total energy within the system remains constant.

5. Why is the Law of Conservation of Energy important in understanding gravity?

The Law of Conservation of Energy is important in understanding gravity because it explains how gravity behaves as a conservative force. By following this law, gravity obeys the principle of energy conservation and does not violate any fundamental laws of physics. This helps us understand and predict the behavior of objects affected by gravity, and how energy is transferred within a system. Without this law, our understanding of gravity and other physical phenomena would be incomplete.

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