# Tag Info

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The short answer is, yes. The slightly longer, but slightly more accurate answer is yes, but not noticeably. As you say, increasing humidity by evaporating existing water will cause the mass of the vapor to move to a greater distance from the earth's center, and this will increase the moment of inertia, reducing the rotation rate. Consider that the ...

1

CuriousOne writes in a comment that single atom is visible "if it is illuminated properly," which is correct. It's possible to construct a trap for a single atom with transparent windows, and to illuminate that atom so that it fluoresces. Note that this was impossible thirty years ago and is nontrivial today. What your textbook author almost certainly has ...

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break earth into 2 parts in which each part is nearly equal to half of volume of the earth Yes and no. No, as in you can't neatly split the planet in half. Most of the earth is liquid and will re-form once the cutting device has passed through it. Much like cutting pudding. Yes, if you want 2 half-earth balls when you are done and don't care about the ...

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Stokes Law is not going to apply in this situation because the water flow around the ball will be turbulent not laminar. The way to see this is to calculate the Reynold's number. For a sphere this is approximately given by: $$Re \approx \frac{\rho_wdv}{\mu}$$ If we feed in $\rho_w = 1000$ kg/m$^3$, $d = 0.00317$ m, $v = 37$ m/s and $\mu = 0.001$ Pa.s ...

4

One can answer this question by calculating the energy needed to shift half the Earth's mass so that it is infinitely far from the other half. Let's calculate the gravitational potential energy released as we create a planet: assuming a constant density $\rho$, when the planet is growing and of radius $r$ and thus of mass $M(r)=\frac{4}{3}\pi\,r^3\,\rho$, ...

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No, because the vast majority of the planet has a molten interior and where it is not in the liquid phase it is held in solid phase by the internal pressure. You could maybe disperse it into space with a big enough bomb, but not actually break it into two parts.

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There is no fundamental physics reason why carrying a bag should use more energy than wheeling it. Whether you be carrying a bag or wheeling it, you are essentially sliding it along a line of almost constant gravitational potential (aside from a little jiggling up and down with your stride), so the bag's total energy isn't changing and in theory does not ...

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As far as I know, there is no data to calculate the drag effects of the atmosphere at these speeds. The Pascal-B shot of Operation Plumbob did, apparently, launch a 1-ton steel plate at 6 times escape velocity. https://en.wikipedia.org/wiki/Operation_Plumbbob Nobody has the faintest idea of whether or not it actually made it out of the atmosphere, although ...

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Let's take this in steps. First - assume there is zero friction between the bottom block and the tower, and between the bottom block and the ground. If I move the block "infinitely quickly" the tower will have had no time to tilt at all, and it will drop vertically (and remain upright). This tells me there are two things to consider: the time take to ...

1

Let's solve this in two parts. First, I will calculate how fast you need to go at the bottom of the swing in order to be able to make a complete loop (without the rope going slack). Next, I will estimate whether you can achieve this speed by "pumping" - that is, moving your center of gravity around to increase your speed. Part 1: speed needed The velocity ...

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The fictitious acceleration due to Earth's spin can be found using centrifugal acceleration, $$a_{ca} = \omega^2 r,$$ where $\omega$ is Earth's angular velocity (roughly $7.292\cdot10^{-5}\ rad/s$) and $r$ the shortest distance between you and the axis of rotation of Earth. The direction of this acceleration will be aligned with the shortest distance ...

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I think, John Rennie's answer is far far better than anything I can do, but I'm going to give you the "universe for dummies" answer anyway. Mass of the observable Universe: 10^53 KG Density of the observable Universe: 9.9×10−30 g (equivalent to 6 protons per cubic meter of space - not very dense.) Source (Wiki): ...

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Assuming you wrote a realistic SF story, you need to allow time to accelerate to the velocity of say, 95% of the speed of light. As CuriousOne points out, that's asking a lot in the following areas: in terms of time, (even if you could get to very high speeds, your characters would be dead , due to long acceleration times way before relativity effects ...

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