Questions tagged [newtonian-gravity]
This tag is for questions regarding the Newtonian model of gravity in which the force between two objects is given by $~GMm/r^2~.$ It is a natural phenomenon by which all things with mass or energy – including planets, stars, galaxies, and even light – attract one another. On Earth, gravity gives weight to physical objects, and the Moon's gravity causes the ocean tides.
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Regarding the objects in free fall in the ISS
There are lots of information about this topic, but I'm still greatly confused about something:
Astronauts in the ISS are in free fall all the time because they have only gravity acting on them, but ...
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Tidal forces between Moon and Earth
I started studying about gravitation recently and I came across the fact that when finding the gravitational force between the earth and some point mass in space, we can consider the mass of the earth ...
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Angular momentum of the center of mass of yo-yo reaching the end
I am a physics undergrad, and I know only a basic stuff about the subject.
Yesterday, I was taught about the angular momentum of a yo-yo and
my professor said that when the yo-yo hits the end of the ...
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Rocket equation non-constant gravity
I am currently trying to teach myself differential equations and wondered about the following problem.
You have an object (a rocket of constant mass $m_r$) and initial velocity $v_0$ that tries to ...
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Where am I wrong in proving that force perpendicular to motion increases speed and kinetic energy? [closed]
Lets think of a helicopter flying at some height $h$. It throws a food packet to a person on the ground from air. Let's neglect the air drag.
The food packet is thrown only with some velocity $v_x$ in ...
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Question about Lagrange's solution for the three-body problem
The original text in my textbook, written in short:
"By Newton's second law,
$$\ddot{\mathbf{x}}_1=-Gm_{2}\frac{\mathbf{x}_1-\mathbf{x}_2}{|\mathbf{x}_1-\mathbf{x}_2|^3}-Gm_{3}\frac{\mathbf{x}_1-...
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Trajectories of projectile based on different speeds of projection [duplicate]
So my teacher was teaching gravitation and an interesting fact that he mentioned was the trajectory of a projectile projected from Earth at a speed equal to escape velocity, is parabolic.
Also, he ...
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Pseudo Orbital motion only due to Coriolis force
Planet, say of mass M and radius R is rotating with some angular velocity ω and a object of mass m (initially on the surface and rotating with the planet) was launched with velocity v vertically ...
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Projectile/orbital motion over very long distance
We know the optimum angle for greatest horizontal displacement when launching an object with projectile motion is 45 degrees.
How to solve the angle when it is real long distance around the earth ...
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Integrating acceleration + escape velocity over distance [closed]
I am not sure how to title this question so apologies if it's inaccurate.
If I throw an object at thrice the escape velocity of earth, what would be its velocity very far away from earth, (at a ...
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The impossibility (or possibility) of solving $N$-Body problem
One can obtain the solution to a $2$-Body problem analytically. However, I understand that obtaining a general solution to a $N$-body problem is impossible.
Is there a proof somewhere that shows this ...
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What is the gravitational force acting on a massless body?
It's a well known fact that acceleration due to gravity is independent of the mass of the accelerating body, and only depends on the mass of the body it is accelerating towards and the distance from ...
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Gravitation in a Toroidal Planet
I recently took interest in toroidal planets, not because they necessarily exist, but rather due to a more practical result (it can be easily represented with a rectangle). This got me curious about ...
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Toroidal Planets
I have read online in numerous places about the possible existence of toroidal planets, and I most people seem to believe that they could exist, but they also have no evidence to support this claim. I ...
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The topology of planets [duplicate]
Just a curiosity:
Let $g \in \mathbb{Z}_{>0}$. Is it possible for a planet of topological genus $g$ to exist? For example, is there any contradiction (from the point of view of physics) in assuming ...
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