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You can only know that a Foucalt pendulum demonstrates the rotation of the earth by way of astronomical observations - that is, it is by observing the motion of the stars that you can tell how long the day is. That being so, you can determine that the motion of a Foucalt pendulum corresponds to the position of a distant star, that is, it corresponds to a ...


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The simple answer: Satellites do feel this force, but obviously don't get ripped apart. The tidal forces are simply too small (for the satellites' materials) to actually rip them apart. The Why: Tidal forces happen because one side of an object feels such a larger huge difference in force than the other side. The magnitude of the force not only has to deal ...


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As soon as the ball is released from the rod, it starts going in a tangential direction. Since there are no external forces on the system, the linear momentum of the system (ball + motor) must be conserved and the motor starts moving in the opposite direction of the ball with some velocity (depending upon the masses of ball and motor), so that the linear ...


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from a, b and c: An electromagnetic field is propagating by changing the field that's generated by electrically charged particles pass through the air and the space that is devoid of particles of space. An electromagnetic wave propagates, not an electromagnetic field. An EM wave is a propagating disturbance in the existing electromagnetic ...


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The electromagnetic field is mediated by the exchange of virtual photons. This is described by Quantum electrodynamics. It's this exchange that bridges the gap of empty space. I think the answer to this question has a pretty good representation of how an electromagnetic field propagates (at the speed of light) in vacuum.


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I am going with no. If this was a question of sound spreading with an inverse square law, the answer would be yes. Place a cymbal at a distance where it has the same apparent diameter as the sun. On a quiet day, it would be audible. Place 4 cymbals at twice the distance. It would be just as loud. Repeat this idea at the distance of the sun. If the ...


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Let me give a more detailed back-of-the-envelope approximation, which might actually be able to decide, given the conditions of the problem, if we would be able to hear the sound of Sun. Assumptions: The space between Earth and Sun is filled with uniform air. This is a non-physical assumption. It basically means we are ignoring the gravitational effects ...


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Sound, in simple words is vibration of air. So in theory yes, we should hear the Sun if there was a medium like air that could transfer the vibrations. That's just my opinion, of course I can be wrong as this is purely theoretical question and answer.


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It depends on what you call a medium; I assume you refer to matter as a medium. Then, roughly speaking: yes, there is radiation, like light, or heat radiation, that can exist without matter as medium. I think you could call this "energy" in this sense. You can transfer light through a vacuum, of course. The sun, fire or burning magnesium are about matter ...


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Like a rocket provides oxygen to burn fuel in space, so the sun provides its own energy. Like you, I'm not necessarily convinced the space in an of itself it not a medium since light travels at a constant speed within it and matter is capable of traveling within it. Planets bleed their own atmospheres into space as well. Please see the about page: ...


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Yes, it's a misconception, or not - or both. What do you call "matter"? Let's call matter particles with a rest mass. So, everything that's made up of elementary particles is matter. Now here's the catch: To the best of our knowledge, elementary particles are pointlike, i.e. they really don't have any extend in space, they don't really "occupy" any space. ...


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Inside the solar system the solar wind consists of sub-atomic particles that form a plasma, one of the four states (phases) of matter along with solid liquid and gas. Plasma is basically a gas of charged particles--normal gas laws don't apply as moving charges create magnetic fields and magnetic fields influence moving charges, thermodynamic gas laws assume ...


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In a sense this could be an interpretation of gravitational waves. In this case, anything with energy or mass or momentum (relating by the stress-energy tensor in GR) could bend space-time producing gravitational waves. hopefully I'm understanding you correctly.


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Yes, if you throw a ball in a vacuum its spin will not affect its trajectory. This isn't because there's a liquid with no viscosity, it's because there isn't anything at all!


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Considering that hitting a 1mg grain of dust at 0.1c speed would release the energy equivalent to an explosion of a 200 kg bomb, I really would not hold my breath. The only way I can imagine interstellar travel is as a swarm of nanobots. They would be sent on their way, and would have to be somehow decelerated at the destination. They would not carry fuel, ...



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