All Questions
Tagged with newtonian-gravity potential
123
questions
5
votes
2
answers
1k
views
Why does field strength follow the inverse square law but potential does not?
Either in a gravitational or electrical field, let's say an electrical field, the electrical field strength follows the inverse square law. This is fairly intuitive just due to the geometry of the ...
- 109
1
vote
2
answers
195
views
Electric voltage versus gravitational voltage across a unifom field
Let us say we have a uniform electric field, like between two charged plates separated by a distance $d$.
The formula for the voltage between the plates is $\Delta V=Ed$.
But what is the value of ...
- 527
0
votes
1
answer
6k
views
Relationship between gravitational potential and gravitational field strength
So I was trying to think of a reasonable relationship between gravitational potential and gravitational field strength. However, I'm not sure whether this is correct:
$g=\frac{GM}{r^2}$ where $g$ is ...
- 117
2
votes
1
answer
173
views
Gravitational Potential Derivation
The definition of Gravitational Potential at a point is the work done per unit mass in moving it from infinity to that point. However the work is positive and if you perform the integral you get a ...
- 31
1
vote
2
answers
301
views
Newton's Universal Law of Gravitation doubt
The Universal Law of Gravitation states that the module of the force, $F$ is
$$F = \frac{GmM}{r^2},$$
where $m$ and $M$ are the mass of the two objects and $r$ is the distance between the two objects....
- 179
1
vote
2
answers
3k
views
Direction of gravitational field given equipotential lines
I've attached the question as an image below as it's a graphical question.
It simply states:
"The diagram shows equipotential lines near a group of asteroids. Which arrow shows the direction of the ...
- 17
2
votes
2
answers
2k
views
Is a *difference* of potential energy relative to a frame of reference?
If we consider an electrical field, or a gravitational field, and two points in this field, is the difference of potential between this two points depending of a frame of reference ?
It seems to me ...
- 55
1
vote
2
answers
950
views
Calculation of Gravitational Potential at the centre of the cube [closed]
I came across this problem in a test and have been able to come up with a solution however I am unsure if it is correct.
I started by building a cube of twice the initial dimensions to bring point P ...
- 141
3
votes
2
answers
4k
views
Does gravity get stronger when you climb a mountain?
As stated in the question title, what happens to the strength of the gravitational field (or equivalently, your weight) as you climb a hill or mountain? Would a weighing scale show that you were ...
- 161
6
votes
5
answers
3k
views
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 $M$. ...
- 443
7
votes
2
answers
1k
views
What is the physical reason for why gravitational potential (or electrical potential) due to two masses at a point can simply be added algebraically?
The simple explanation that textbooks and the internet say is that "gravitional potential is a scalar quantity hence can be added algebraically".
However, I'm not sure if it is that simple. Take for ...
- 797
0
votes
1
answer
29
views
Gravitational Potential outside thin shell
Here's the first part of the proof in Feynman's lectures:
\begin{equation*}
dm=2\pi y\mu\,ds=\frac{2\pi y\mu\,dx}{\sin\theta}=
\frac{2\pi y\mu\,dx\,a}{y}=2\pi a\mu\,dx,
\end{equation*}
I don't get ...
- 29
2
votes
1
answer
159
views
$\mathbf{g}(\mathbf{r})=-\boldsymbol{\nabla}\psi(\mathbf r)$: searching for a minus sign error
Consider the following figure
where $R=\sqrt{(x-x')^2+(y-y')^2+(z-z')^2}=|\mathbf{r}-\mathbf{r}'|$ is the module of the $\mathbf{R}$ vector depends not only on the location of the $P$ point but also ...
- 2,547
2
votes
3
answers
364
views
What is actually Gravitational potential?
Gravitational potential is work done by gravitational force to bring unit mass to its field from infinity.
but how can gravitational force work there? I mean, in infinity? As it can only work at his ...
- 29
0
votes
1
answer
440
views
Finding equipotential surfaces of gravitational field
Consider a point $A$ located in New York city. How to find a point $B$ located in Chicago with the same gravitational potential as $A$? Is there any practical method of doing this? And with what ...
