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7

No, it won't. In a bucket, the gravitational forces acting on each particle of the fluid are parallel (if the the bucket is small with respect to the Earth radius, which I think we can always assume). Without rotations, the fluid will form a plane surface inside the bucket (which is neither convex nor concave). This surface coincide with a surface of ...


4

Occam suggests that the sounds are either able to be explained as typical noises that 'just happen' or are hoaxes. It is unfortunately extremely common for a large number of copy-cat reports of major "strangenesses" to occur once something suitably notable appears "on the web". There are numerous web discussions about these "phenomena". This 14 minute ...


3

As Dirk Bruere has pointed out, the mass of the earth's oceans is 1400/5 times the mass of the earth's atmosphere. If 1% of that mass is converted to vapor (and not immediately precipitated out), this implies a mass of water vapor 1400/500 times the mass of the atmosphere, or 2.8 times greater. Ignoring the slight change in gravitational attraction of the ...


2

The same effect does occur, but the magnitude is very small compared to the natural curvature of the earth. The follow up question would be, could there be a planet on which the ocean formed a concave surface at the poles? Intuitive answer If the water wants the flow away from the poles to the outside so badly that it forms a concave surface it will want ...


2

The Saturn V threw roughly $m=3\times 10^6{\rm kg}$ out its hinder end at a speed of about $v=3{\rm km\,s^{-2}}$. The angular momentum of this mass thrown tangentially to the ground about Earth's center is then $R_\oplus\,m\,v$, where $R_\oplus$ is the Earth's radius. Assuming the Earth to be uniformly dense for a rough figure, its mass moment of inertia ...


2

Imagine wind blowing along a plane with the air by the ground all a nice and steady temperature. Now this wind encounters a mountain range, so is forced upwards. The pressure is lower at higher altitude since there is less remaining atmosphere above it. The temperature of gas decreases when the pressure is lowered, which is why this same air gets ...


2

An atmosphere in absolute equilibrium in fact is isothermal (see below for more detailed analysis of your cannonball). However, if the atmosphere is mixed by wind, gas expands and contracts adiabatically. If the mixing is fast enough, it obeys relatively well the adiabatic invariant, which multiplied by suitable form of ideal gas law ($(T/(pV))^\gamma = ...


2

Why it is colder in mountains, at high altitudes? One answer is that mountains on Earth aren't all that tall. An impossibly tall mountain would see temperatures vary with altitude as depicted below. Tall as it is, even Mount Everest doesn't extend into the stratosphere. This is a question about the lowest layer of the atmosphere, the troposphere. ...


1

You are going in the right direction: Since on a different latitude the pendulum will be rotating with earth, it will change the rotation due to the coriolis force. As the pendulum being at a pole is an extreme case, so is the position at the equator: Here there's no reason for the rotation Foucault's pendulum is famous for. An intuitive guess would ...


1

When our solar system formed it had a certain amount of intrinsic angular momentum. As it collapsed over time it began to spin faster like an ice skater that brings her arms in. Our planet, Earth, was formed in this cloud. It too is the product of that spinning gas cloud long gone. So the Earth retains the angular momentum of the matter that formed it. The ...


1

I think the answers are all correct, but it's worth pointing out that a lot of Earth's rotation came when it was hit by Theia. If Theia had hit the earth's other side, the Earth just might be spinning clockwise, against the spin of all the other planets.


1

The equation you cited makes use of "big G", the universal gravitational constant. Generally, this equation is used if you want to calculate the attractive force between two bodies, such the moon and the Earth, or a satellite and the Earth, or the Earth and the Sun, or if you want to calculate escape velocity from he Earth's gravitational field. The center ...


1

Gravitational force may not need to be continually produced by anything. For example, the Earth is here and it is not produced continually by anything. The same may hold for gravity; it just is there near all the bodies and it is not being produced. Just because we cannot see gravity does not mean it is any less real than the Earth.


1

The air becomes colder because of the ideal gas law, $PV=nRT$. where $P$ is pressure, $V$ is volume, $n$ is the number of moles of the gas, $R$ is the ideal gas constant, and $T$ is the temperature of the gas in Kelvin. If we rearrange $PV=nRT$, we can solve for $T$. By looking at $T=\frac{PV}{nR}$ you can see that reducing pressure will reduce the ...


1

Your reasoning demonstrates precisely why formal logic alone is insufficient to study nature. In particular, it lacks the ingredient of inference that is a cornerstone of empirical science. A cosmic ray striking the Earth is not some random act of the gods that can have any imaginable consequence whatsoever. It is a cosmic ray striking the Earth. Sure, by ...


1

as molecules jump higher, they loose energy/speed due to gravity. This results in molecules slower at heights and therefore you have lower temperatures at the heights, boy. Molecules do not jump up, they scatter off each other every which way. The difference in gravitational energy within the nanometers of the molecule's path before a scatter on ...


1

I think (and somebody correct my math if I get this wrong), there is a tiny effect, and, no, it's not concave ever. If the Earth was a flat rotating disc, then this would happen. The Earth's sphere shape makes the 2 dimensional math inaccurate, but lets look at the 2-d math anyway. Newton's bucket mathematics Source: ...


1

@Bernhard has a point: because the Earth is an oblate spheroid with a relative error of ~0.5%, rather than a true sphere, you will never see it as a "uniform sphere" if your tolerance for relative error is smaller than that. But I see you as talking about terrain, rather than the overall shape of the Earth, so for my comment I will assume that the Earth is a ...


1

The water is not in a bucket it is free to move around. An it does move to the equator because of the earths rotation (Here also gravitational forces from the moon play a role). So no I don't think they would see a convex surface, not even at a microscopic Level. They would however see that the water surface is a tiny bit less concarve then at the equator.


1

As said in the comments, there are only 4 known fundamental forces, gravity, strong and weak interaction, and electromagnetism. Since we are restricted to low energy classical mechanics, we can ignore two of them, and we are left only with gravity and electromagnetic forces (which includes, among others, magnetostatic and electrostatic forces). Moreover, ...


1

If I understand your question correctly, they do experience a different centrifugal force. They both travel along the equator, with equal but opposite speed with respect to the surface of the earth. But the Earth frame itself is a rotating reference frame. So you could look at the problem in non-rotating frame, where one of the objects has a speed ...



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