All Questions
9
questions
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2
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103
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Defintion of gravitational potential
I am not much clear regarding the defintion of "gravitational potential":
Is the work done for bringing the unit mass from infinity to that point by, gravitaional force or external force? (...
1
vote
1
answer
39
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What energy is transferred into potential? [closed]
This question could be really out of the blue and might receive lots of downvotes, but bugging me quite a time and would appreciate your thoughts easily explained.
We know that when we do work against ...
1
vote
1
answer
307
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Interpretation of gravitational potential in 2+1D
From Gauss's law of gravity reduced to 2+1 dimensions, one can easily show that the gravitational force follows an inverse law, i.e.
$$
\mathbf{F}(\mathbf{r}) =- \frac{G m M}{|\mathbf{r}|}\hat{\mathbf{...
- 111
-1
votes
3
answers
178
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Why gravitational potential away from a planet increases?
textbooks----
"potential increases towards infinity and is maximum at infinity"
But that is true only when we are seeing potential w.r.t Earth
EXPLANATION---------
So , as we know that ...
- 444
3
votes
3
answers
126
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What is wrong with this calculation of work done by an agent bringing a unit mass from infinity into a gravitational field? [duplicate]
Let us assume that a gravitational field is created by a mass $M$. An agent is bringing a unit mass from $\infty$ to distance $r < \infty$, both measured from mass $M$.
The agent is always forcing ...
- 49
2
votes
1
answer
365
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Gravitational potential energy defined as the work done on a mass
Our physics sir made us write that gravitational potential energy is the work done in bringing a mass from infinity to a point without acceleration, but I am confused because if acceleration is $0$ it ...
- 1,200
2
votes
1
answer
173
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Gravitational Potential Derivation
The definition of Gravitational Potential at a point is the work done per unit mass in moving it from infinity to that point. However the work is positive and if you perform the integral you get a ...
- 31
-3
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1
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1k
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Deriving relation for gravitational self energy
My book says $U_{self}=\dfrac{-GM^2}{2R}$ for the hollow sphere, I tried deriving it as:
Suppose mass constructed is $m$, Work done on bringing mass $dm$ from $\infty$ to $R$ is $$dW=dm(V_{R}-V_{\...
- 299
1
vote
4
answers
944
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Which would require less energy to rub the black board?
I have been thinking about a problem that would give teachers and students that rubs blackboard the optimum way to rub the chalk off the blackboard.
The problem is as follows:
"A man is going to rub ...
