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anand
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Why does every action have an equal and opposite reaction?
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Originally posted by anand
Why does every action have an equal and opposite reaction?
Thats a tough question because it is something that seems (to me at least) to be self evident: It just does. So let me turn it around - is there something that leads you to believe it wouldn't?Originally posted by anand
Why does every action have an equal and opposite reaction?
Originally posted by anand
Heh heh.Actually I am a high school student.So, I don't really understand what you mean.Could you please explain?Any way,thanks for replying.
Originally posted by anand
Why does every action have an equal and opposite reaction?
Originally posted by anand
Why does every action have an equal and opposite reaction?
Originally posted by Ambitwistor
Specifically, every force has an equal and opposite force. This is because of conservation of momentum. Force is a change in momentum over time. If momentum is conserved, then it cannot change with time. That means that if you apply a force to change the momentum of part of a system, there must be an opposing change in momentum (force) to keep the total change in momentum equal to zero.
So, your question has been reduced to the question, "Why is momentum conserved?" If you study the Lagrangian formulation of mechanics, you learn that conservation laws are due to symmetries. (This is known as "Noether's theorem".) In this case, the law of conservation of momentum is due to a spatial translation symmetry. In plain terms, the outcome of an experiment should not depend on where it is performed. So if you move from one place to another ("translation in space"), the laws of physics are unchanged ("the laws of physics are invariant under spatial translation"). Noether's theorem says that there must then be a conserved quantity, which we call "momentum".
So, your question has been further reduced to the question, "Why are the laws of physics the same at all locations?" We don't know. Maybe they aren't ... they are as far as we know, but we can't know for sure.
Originally posted by Rybo
"Conservation of momentum" sounds much like "conservation of energy."
I would informally extrapolate from those statements a "conservation of inerta" as well.
Why these three and others are conserved is due to the physical Universe being a finite integral whole.
Why are the laws of Universe the same everywhere in Universe as far as we know?
Beacuse if they weren't the integrity of our physically finite whole of Universe would not exist.
That isn't true for static forces as there is no momentum or energy change.Originally posted by Ambitwistor
Specifically, every force has an equal and opposite force. This is because of conservation of momentum. Force is a change in momentum over time.
Originally posted by russ_watters
That isn't true for static forces as there is no momentum or energy change.
Newton's Third Law of Motion states that for every action, there is an equal and opposite reaction.
This law applies to everyday situations by explaining the cause and effect relationship between two objects. For example, when you push against a wall, the wall pushes back with equal force.
This is because of the conservation of momentum, which states that the total momentum of a closed system remains constant. Therefore, when one object exerts a force on another, the second object will exert an equal and opposite force back in order to maintain the total momentum of the system.
Yes, this law is applicable in all situations where there are interactions between two objects. It is a fundamental law of physics and applies to both macroscopic and microscopic interactions.
Yes, this law can be observed in space. For example, the force of a rocket's exhaust pushing downward causes an equal and opposite force that propels the rocket upward. This law also explains the motion of planets and stars in space.