Questions tagged [earth]
Earth is the planet on which we live, the 3rd planet from the Sun. Questions using this tag should be about Earth the planet and not Earth-like planets nor earth, as in dirt or soil.
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How does gravity work underground?
Would the effect of gravity on me change if I were to dig a very deep hole and stand in it? If so, how would it change? Am I more likely to be pulled downwards, or pulled towards the edges of the hole?...
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Why doesn't the Moon fall onto the Earth?
Why doesn't the Moon fall onto the Earth? For that matter, why doesn't anything rotating a larger body ever fall onto the larger body?
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Would you be weightless at the center of the Earth?
If you could travel to the center of the Earth (or any planet), would you be weightless there?
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Do mankind and manmade activities/constructions have any effect on the rotation of the Earth?
We walk or ride on our vehicles to our destinations daily. Does our movement have any effect on the rotation of the earth according to Newton's law? What will be the effect if we move all the peoples ...
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Why is Earth's gravity stronger at the poles?
Many sources state that the Earth's gravity is stronger at the poles than the equator for two reasons:
The centrifugal "force" cancels out the gravitational force minimally, more so at the equator ...
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Is acceleration due to gravity constant?
I was taught in school that acceleration due to gravity is constant. But recently, when I checked Physics textbook, I noted that
$$F = \dfrac{G m_1 m_2}{r^2}. $$
So, as the body falls down, $r$ ...
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How fast a (relatively) small black hole will consume the Earth?
This question appeared quite a time ago and was inspired, of course, by all the fuss around "LHC will destroy the Earth".
Consider a small black hole, that is somehow got inside the Earth. Under "...
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Near Earth vs Newtonian gravitational potential
Newton's Law of Universal Gravitation tells us that the potential energy of object in a gravitational field is $$U ~=~ -\frac{GMm}{r}.\tag{1}$$
The experimentally verified near-Earth gravitational ...
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What is the general relativity explanation for why objects at the center of the Earth are weightless?
The idea that as you move through the earth you get a symmetric cancelling of gravitational acceleration which approaches zero acceleration due to gravity at the center of the earth makes a lot of ...
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What is the simplest way to prove the Earth is round?
Assume you've come in contact with a tribe of people cut off from the rest of the world, or you've gone back in time several thousand years, or (more likely) you've got a numbskull cousin.
How would ...
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Can the Earth's magnetic field be used to generate electricity?
Since the Earth has a magnetic field, can it, in theory, be run through a conductive metal coil to create electricity?
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Why has Earth's core not become solid?
The Earth is billions of years old, yet its core has not yet cooled down and become solid. Will this happen in the foreseeable future?
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What is the net charge of the Earth?
This question arose in a seminar today about the solar wind...
This is my vagueish understanding of the problem - please correct if you see errors!
The 'classical' picture of atmospheric electricity ...
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Why and when can the Earth be considered an inertial reference frame?
The question has been asked (e.g., here and here), but I would like to get a more definitive and mathematically formal answer.
The Earth rotates around its axis, around the Sun, and participates in ...
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Why can't we feel the Earth turning?
The Earth turns with a very high velocity, around its own axis and around the Sun.
So why can't we feel that it's turning, but we can still feel earthquake.
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