Questions tagged [laws-of-physics]
DO NOT USE THIS TAG just because the question deals with a law of physics!
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Mass/weight in 2 places at the same time
Though it may seem like it is not, this is a genuine question of which I cannot find the answer online. The situation of how the question arose may make it seem otherwise.
I monitor my weight every ...
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The independence of friction on area of surfaces in contact
Why is it said that as long as the normal contact force remains the same or constant, the frictional force is independent of the area of the surfaces in contact?
Does it mean when the normal force ...
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Acceleration on a system of two particles
Let's imagine we have a system of two particles. If we apply an external force to only one of the two particles where the external force is greater than the internal force, then due to internal forces,...
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What would the universe look like if it had undergone a false vacuum decay in the past?
Inspired by "if a metastable de Sitter space lasting for cosmological durations really is impossible in string theory, then dark energy needs to be explained in some other way, e.g. via ...
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Why does the ball in Galileo's double inclined plane experiment reach the same height?
Why does the ball in Galileo's double inclined plane experiment reach the same height? I know how to show it by energy conservation law but am unable to prove it by the equations of motion. Can anyone ...
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All possible models to explain the hierarchy problem?
There is an interesting paper by Arkani-Hamed and collaborators (https://arxiv.org/abs/1607.06821) to address the hierarchy problem.
There, they consider many possible models of fundamental particle ...
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Is math really fundamental or would it not matter if physics did not depend on math? [closed]
Can you disprove this please because it's been bugging me and I don't know much about physics at all as I'm only in 10th grade. It's one of those weird thoughts but I would like confirmation to keep ...
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Tree falling without inertia while people stay suspended in air for a split second due to inertia
I recently saw a video ( watch it 0.5x speed ) of a slanted coconut tree on the bank of a river in India breaking due to the weight of the kids who climbed on it.
The tree seems to have broken near ...
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Why don't the net acceleration of the truck becomes zero after hitting the man? [closed]
Imagine, there is a truck of mass 'm' accelerating with an acceleration 'a', this means that the truck definately carries some force 'F'(let). Now, imagine the truck collides with a man standing ...
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Can we have laws of physics without any laws of conservation?
The famous physicist John Archibald Wheeler proposed that there were no fundamental laws and that eventually, at very high energies, they would be broken. He proposed this conjecture when it was ...
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Do symmetries indicate that laws of physics are invariant?
Concerning symmetry in fundamental physics, it is usually said that symmetry indicates that laws of physics are invariant independently of something
For example, time translational symmetry indicates ...
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Axiom $\equiv$ postulate? [duplicate]
Is there any difference between an axiom and a postulate?
I would say that while an axiom is any proposition fixed as true without premises in a theory, a postulate is (also according with its ...
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What if the universe was not uniform...?
In this popular science article, they say that if our universe resulted to be non-uniform (that is highly anisotropic and inhomogeneous) then the fundamental laws of physics could change from place to ...
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Entropy change in free expansion
In the textbook of thermodynamics by Zemansky, I came to free expansion. If $dQ=0$ (because there is no heat exchange between system and surroundings), entropy should be $0$ as $dS=dQ/T.$ Now, the ...
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Why can't we run the laws of physics backwards and forwards in time infinitely?
So assuming we know all the laws of physics in differential equation form, and I have an estimate for the current large scale state of the universe (whatever standard assumptions/data cosmologists use ...
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