# Tag Info

5

No, these building are still tiny compared to earth's crust mass distribution. One would need to build whole mountain ranges to detect changes in earth gravity field with high precision instruments. And even those wouldn't changed earth orbit measurably because even a mountain range is tiny compared to the mass of the whole earth. However mountain ranges ...

-1

The centripetal force we feel on the surface would immediately disappear, causing us to feel lighter. The centripetal force is equal to $E=mv^2/r$ and the acceleration is given by $a=v^2/r$. This results in a reduction of the acceleration towards the earth’s centre, also known as gravity. Therefore we would feel lighter

0

Isostasy is an important geophysical concept needed to understand the relationship of gravity, mass distribution, and first-order topography of the earth. The elevation of the ocean basins is lower than the continents because oceanic crust is thinner and more dense than continental crust. The gravity anomaly over a mountain range is less than you might ...

1

You are quite correct that the position of the tectonic plates does affect Earth's gravity. The most accurate measurements of this were made by NASA's GRACE satellites. The results are generally shown as a geoid, that is a deformed globe showing where gravity is high and where it's low: Note the scale is exaggerated to highlight the differences. The scale ...

0

It depends what accuracy you want to say things are equal. We often say $g=9.81 m/sec^2$ at the earth's surface and don't worry about it. Altitude and latitude affect this at the $0.3\%$ level. You can look at Wikipedia to start. Continental crust versus ocean crust is lower, but noticeable.

0

I'm not an expert in this but roughly gravity depends on the distance to the center of the earth and, in a first approximation, this depends on two different factors. First, and most importantly, the fact that the earth is not perfectly spherical but has an oblate shape because of its rotation. Second the altitude of a particular place. So I believe that ...

0

Natural circulation in tubes is driven by pressure gradient between warmer and colder parts of the fluid. The pressure gradient results from density gradient, which is induced thermally by heating/cooling the tube at different points. However, tube dimensions You've set, make it a very complex problem, probably impossible to solve. Normally models have to be ...

2

According to E. V. Petjeva (2011), the measured rate of change of the Earth-Sun distance (astronomical unit) is (1.2 +/- 3.2) cm/yr, with the uncertainty value representing 3 standard deviations. In other words, any change is within the uncertainty of the measurement. She specifically addresses the Krasinsky and Brumberg value. E. M. Standish has also ...

1

Here's a contrarian opinion: there's no such thing as seeing a fully rounded earth! Standing at the top of a high building, you look out from the center of a circular (fully round?) disc (with a hump from the spherical earth). The edge of that disc is the horizon, the farthest point you can see in any direction. Since you are above that rim, you are ...

5

This will be limited by our field of view (FOV). I couldn't find a better source, but Wikipedia says the vertical range of the field of view in humans is typically around 135° and the horizontal range around 180°. So for the Earth to be entirely within your field of view it will be limited by your vertical range. And by using a little bit of geometry you ...

0

I believe that the commonly accepted definition of weight is ''the force of gravitational attraction that the earth exerts on your body'' University Physics, Young and Freedman, 11th edition, page 120 So I would say no, the weight cannot be affected by any electromagnetic fields, by the true definition of weight. If by weight you mean the number read ...

3

The curvature of the Earth is not enough to really 'curve' any object that's city-sized or smaller. The reason for this is that the radius of the Earth is really big.[citation needed] To make this more precise, say you make your chair one metre wide, and you have the edges pointing towards the centre of the Earth. You can then form an isosceles triangle ...

3

This is due to Rayleigh scattering, i.e. the shorter wavelengths (those near the violet end of the visible spectrum) are more deflected by dust particles than the longer wavelengths (those near the red end of the visible spectrum). When the sun is near the horizon, it the path of the light through the atmosphere (and in particular through layers which have ...

2

The Wikpedia article on solar cell efficiency gives a number of reasons that solar cells are less than 100% efficient. One of the large ones is the thermodynamic limit-a photon of less energy (longer wavelength) than the silicon band gap cannot produce an electron and one with higher energy can only produce as much voltage as the band gap. Even if you ...

1

No energy conversion process completes at 100% efficiency. Using the sun, gasoline or nuclear, none of these will generate power at 100% of total potential power available. That figure of 1KW/m^2 is for total available light energy correct? Due to how solar panels work (I don't think I have enough knowledge to speak on this part directly) solar panels are ...

6

Let's put a more precise description to the other answers, particularly Neil's. First, note that there is a Gauss Law for static gravitational fields, owing to the inverse square nature of the static gravitational attraction. See this answer here and note that the argument it makes uses only the inverse square dependence. (Actually, the Gauss law also holds ...

0

Here is my answer i figured out earlier when i posted this question (with no answer) If you took an elevator through the earths core: Gravity would gradually feel weaker and weaker, and you would feel more and more weightless as you close in on the core. Because in the core: The mass of the earth is more or less equal in all directions, and it would "pull" ...

3

Please take a look at this link Hole through the earth. It seems that the physics of passing through the earth would not be as it was implied by Total Recall in which gravity switches suddenly. While gravity is normally affected by radius squared (gravity much stronger proportionally as you approach a gravitational body), inside a gravitational body, its ...

5

As you already suspected, your weight would gradually decrease as you descend into earth. Technically, at the center of the earth you should feel no gravitational force (from earth, I don't know how strong additional sources of gravity affect us, but my guess would be that they are negligible). Once you start "rising" on the other side, gravity would slowly ...

-2

I think the moon and sun do affect the weather more than we are led to believe, the moon is getting farther away and the sun is getting larger, these both must have an impact on earth. The suns solar flares and mass corona ejections also play a part. I believe small changes in the moons orbit and distance and the suns swelling has a bigger impact on the ...

0

I believe that the reason why specific impulse has the units seconds is to prevent confusion between people who use the metric or imperial system. Because the "efficiency" of a rocket is actually indicated by the effective exhaust velocity: $$v_e=\frac{F}{\dot{m}}$$ However this has an unit of length, which is different between the metric and imperial ...

0

The Wikipedia article you link states: For all vehicles specific impulse (impulse per unit weight-on-Earth of propellant) in seconds can be defined by the following equation ... The quantity $\dot{m}g_0$ is the weight flow rate of the propellant when the local gravitational acceleration is $g_0$, so the weight-on-Earth bit of the definition implies ...

Top 50 recent answers are included