Questions tagged [escape-velocity]
The velocity an object must travel to successfully exit the gravitational influence of a body.
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Does a gun exert enough gravity on the bullet it fired to stop it?
My question is set in the following situation:
You have a completely empty universe without boundaries.
In this universe is a single gun which holds one bullet.
The gun fires the bullet and the ...
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Why doesn't hydrogen gas exist in Earth's atmosphere?
The root mean square velocity of hydrogen gas at room temperature is:
Gas constant: $R=8.31\ \mathrm{J\ K^{-1}\ mol^{-1}}$
Molar mass of hydrogen gas: $M=2.02\times10^{-3}\ \mathrm{kg/mol}$
$$\begin{...
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Can you exit the event horizon with a rocket?
The reason given in most places about why one cannot escape out from an event horizon is the fact that the escape velocity at the event horizon is equal to the speed of light, and no one can go faster ...
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Escape velocity - Won't the orbital path just become larger with higher initial velocity?
Escape velocity is the minimum speed needed for an object to escape from the gravitational influence of a massive body. However, gravity has infinite range. Object $A$ is always getting pulled by the ...
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When will the Moon reach escape velocity?
From what I know, the Moon is accelerating away from the Earth. Do we know when it will reach escape velocity? How do we calculate this?
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Why is there an escape velocity?
I've been trying for days, but I just can't understand why escape velocities exist. I've searched the web and even this site, and although I've read many explanations, I haven't been able to truly ...
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What is the escape velocity of a Black Hole?
The escape velocity of Earth is $v=\sqrt{\frac {2GM}{R}}$, where $M$ is the mass of the Earth and $R$ it's radius (approximating it as a sphere), and is much less than light speed $c$.
But I want to ...
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I don't understand why escape velocity is necessary [duplicate]
I have read multiple explanations of escape velocity, including that on Wikipedia, and I don't understand it.
If I launch a rocket from the surface of the Earth towards the sun with just enough force ...
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Can a massive object have an escape velocity close to $c$ and not become a black hole?
It is well-documented that a given body has a well-defined Schwarzschild radius, defining a minimum radius for its volume, given its mass, before it becomes a black hole. It is clearly true, also, ...
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Movie Interstellar - Question about Escape Velocity
The movie Interstellar shows people on a water planet where time is dilated so much that 1 hour is equal to 7 years back on Earth. Even though they lift off from Earth using a Saturn-V two stage ...
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If the escape velocity at the event horizon is the speed of light does it mean that slower bodies won't move away at all?
If we say that the escape velocity from a planet is say 10 km/s we think that a slower body will move away from that planet but will be eventually forced to fall back on the planet. In simple words we ...
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Does time stop in black holes? [closed]
I was going through Hawking's incantations on black holes, where black holes get defined as follows:
Black Hole: A region of spacetime from which the escape velocity exceeds the velocity of light.
I ...
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Escape velocity for Schwarzschild metric
I can't fill in the gaps in my solution to this and assistance or a reference would be appreciated.
The question begins with the straightforward derivation of the EoM for a massive particle orbiting ...
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How does escape velocity relate to energy and speed?
I have several confusions regarding escape velocity. I am sure I am missing something(s) obvious or maybe I am taught wrong.
Lets say we throw an object of any mass at exactly escape velocity of ...
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How long must escape velocity be maintained?
Escape velocity from Earth's surface is 11.2 Kilometres/second.
How long would one need to maintain this escape velocity to actually escape Earth's gravitational pull? Must this 11.2 km/s velocity ...
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Can we escape Earth's gravity slowly?
I had a recent conversation with my girlfriend, who is a physics grad student. She was kind enough to listen to me rant about an idea concerning escape velocity. Unfortunately, I am still thinking ...
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Escape velocity to leave the water planet in the movie Interstellar
I saw this question and this question on the site a few days ago. It asks about escape velocity from the water-based planet in Interstellar and whether the black hole had any effect. Now, one question ...
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Escape velocity from long ladder
The escape velocity of earth is roughly $11 kms^{-1}$. However, what if a long ladder was built extending out of Earth's atmosphere and considerably more. Then if something was to climb up at much ...
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What is the physical meaning of the Schwarzschild radius for objects that aren't black holes?
Earth has a Schwarzschild radius of a little less than a centimeter. What does this mean for the matter of Earth's core that is within this radius?
A related question comes up for what happens when ...
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A vertical variation of modern versions of Michelson-Morley
For almost a year now, I have been in the uncomfortable position of having an idea.
However, there is one nice thing about this idea. It makes a concrete, exact and relatively easy to test physical ...
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When did Voyager-1 achieve Solar System escape velocity?
Wikipedia's page on escape velocity puts the escape velocity for an object travelling out of the Solar System at ~525km/s. This figure is slightly higher than the tentative velocity of Voyager-1 at ~...
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Photon Escape Angle From Black Hole
Consider a photon source emitting photons near the surface of a Schwarzschild black hole.
What angle, as a function of the source's radius from the event horizon, must the photons be emitted at such ...
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What is $R$ in the formula for escape velocity?
From the escape velocity formula
$$v_e = \sqrt \frac {2GM}R.$$
Some sources say it is the distance between two objects with mass $M$ and $m$.
Some examples I have read, only used radius of the $M$. ...
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Why can't light travel past the event horizon?
Since the event horizon is defined as the boundary within which the escape velocity is greater than the speed of light, and escape velocity is the speed required for that object to reach infinity away ...
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General relativity vs newtonian mechanics [duplicate]
My high school textbook briefly touched the topic of black holes, and this is how it defined them:
"Consider a spherical body of mass $M$ and radius $R $. Suppose,due to some reason the volume ...
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Shouldn't the escape velocity of earth (with respect to earth) be less than $\sqrt{\frac{2GM}{R}}=11.2\,\mathrm{km/s}$
We know that the escape velocity of earth is,
$$\sqrt{\frac{2GM}{R}}=11.2\,\mathrm{km/s}$$
Where $G=6.67×10^-11$
$M=\text{mass of earth}$
$R=\text{radius of earth}$
So if throw a object ...
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Escape velocity from a rotating black hole
Under Newton, the escape velocity is
$$v_{esc} = \rm c \ \sqrt{r_s/r}$$
where $\rm r_s=2 \ GM/c^2$. In the nonrotating relativistic case (the Schwarzschild case) the radial escape velocity is the ...
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Why is $v=\sqrt{\frac{GM}{r}}$ not a valid equation for escape velocity?
Firstly, I know that the equation for the escape velocity is $$v_{\text{escape}}=\sqrt{\frac{2\,GM}{r}}\tag{1}$$ and understand it's derivation.
The following is such a simple derivation; for a test ...
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Why does the value of the escape velocity approach 0?
I am a little confused about escape velocity. Does the escape velocity always approach 0 as we go to an infinitely far distance even if there isn't any friction?
If so, why does it approach 0? Shouldn'...
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Could we make a trebuchet that could launch objects to a stable orbit?
Inspired by this xkcd, which calculated the energy requirements for accelerating individual humans to escape velocity (regardless of consideration for what that would do to your organs), I am ...
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What is the third cosmic velocity?
I have been studying Gravitation chapter and there I found one term:
Third cosmic velocity which is also known as interstellar speed. So what is it? What it really tells about? I tried to gather some ...
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Escape velocity when Sun is present
When we calculate escape velocity for an object from earth, what we do is, we conserve energy. So if $v$ is the escape velocity, we write
$$-\frac{GM_em}{R_e}+\frac{1}{2}mv^2=0$$ since we are assuming ...
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Rocket launch from a mountain
If we were to build a high speed rail up the side of a mountain like in some Science Fiction movies, what is the velocity needed at the point of leaving the mountain excluding angular momentum from ...
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Where do the gases such as hydrogen and helium end up after leaving the earths atmosphere?
I've heard that gases like hydrogen and helium leak out of the earth's gravity a little by little.
but where are they going? where do they end up after leaving earth's pull?
would the sun pull them ...
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What is the escape velocity of a neutron particle (not neutron star)
I'm not sure if this question makes sense (if not maybe you can explain why)
But if the neutron has mass and have a size, then it should have a escape velocity in the "surface" right?
I know the ...
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Definition of event horizon – gravity around black holes [closed]
Put simpler:
A black hole is surrounded by a 'sphere' where, to an outside observer, the speed of light is (near) zero.
What is the radius of that 'sphere' (for a non-rotating black hole) and how ...
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Why is escape velocity independent of direction of projection?
However, for any body projected with a velocity less then the escape velocity, the final maximum height will vary with variation in angle of projection. But why is this not the case in case of ...
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Orbital escape velocity [closed]
Given a satellite (black) orbiting a planet (green) in a circular motion with $r_o$ being the orbital radius.
The orbital the velocity of the satellite is $v_{orbit}=\sqrt{\frac{GM}{r_o}}$, right?
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How much of the Sun to not evaporate is due to gravity and how much due to magnetism?
As protons and electrons on the sun 'surface' have high kinetic energy something obviously should stop them to go away.Its gravity is very high compared to planets but is this enough as magnetism also ...
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Escape velocity of a rocket standing on Ganymede (Moon of Jupiter) [closed]
I want to calculate the escape velocity of a rocket, standing on the surface of Ganymede (moon of Jupiter) and trying to leave Ganymede.
My thinking was, the kinetic energy $E_{\text{KIN}}$ must be ...
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How far could the LHC "fire" a proton into space if we (outside LHC) ignore all interactions but gravity?
Very simple question, and frankly quite a silly one, but I'm currently writing a lecture for secondary school kids and I'd love to tell them how far the Large Hadron Collider could fire a proton.
The ...
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Why are the dimensions of escape velocity correct?
How does this formula work, from a dimensional analysis perspective?
$$ v_\text{escape} = \sqrt{\frac{2GM}{R}}$$
The way I'm thinking about it is that $G$ is in units $\text{N} \cdot \text{m}^2/\...
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Does it take escape velocity to reach orbit?
I don't comprehend what is meant by "escape"
The internet gives me two meanings thus my following ambiguity:
Does escape velocity mean to reach infinitely far from the earth or to just reach ...
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Escape velocity at an angle
Comparing the work required for a mass to escape the Earth's gravity to the necessary initial kinetic energy gives us the escape velocity from the surface of the Earth of around $11\;\mathrm{km\cdot s^...
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What is the relation between orbital velocity and escape velocity in strongly relativistic situations?
For practical purposes, I'm considering a non-rotating black hole or neutron star, because I find Kerr black holes a little confusing.
The ratio between orbital velocity and escape velocity in ...
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Escape velocity of satellites
I know that the equation for it is $$v^2 = \frac{2GM}{r},$$ and with that, the rocket should be launched at that speed. But could it go much slower spending much more fuel to escape from gravity right?...
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Does the escape velocity of a black hole exceed $c$ *before* a singularity is created?
As an offshoot of the question Can we have a black hole without a singularity? I'm curious if the point of no return at which the massive object is condemned to become a singularity happens before its ...
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Finite velocity at infinite distance
If an object were launched exactly at escape velocity it would have zero velocity at infinity. But what if we launch an identical objects at greater than escape velocity? Apparently it will have a ...
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How does General Relativity explain escape velocities?
In general relativity, objects follow the shortest possible path through curved space-time called a geodesic and that there exists no such force of gravity which pulls objects, it is just because ...
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Does a black hole have any kind of mass?
Currently in my academics I am studying about the Gravitation. In the chapter I came across a term called the Escape Velocity (It's the velocity of any celestial body which is required by an object to ...
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