Questions tagged [potential-energy]
Potential energy is the energy of a body or a system due to the position of the body or the arrangement of the particles of the system.
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From my reference frame, why does the Earth need a huge kinetic energy [$0.5M_E(11200)^2=3.75*10^{32}$ joules] to escape me? [closed]
I wake up screaming into the void, when I see the Earth almost touching me but going away from me at 11.2 $km/s$.
I don't remember what happened before I woke up. I faintly recollect being cannoned up ...
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Can a big mass defect make the mass negative?
Can two particles with small masses and a strong attractive interaction have a total negative mass when brought together?
Let $m_1, m_2$ be the (rest) masses of two particles when infinitely distant. ...
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Generalization of Feynman's derivation of the formula for gravitational potential energy in FLP volume I
In the Feynman Lectures on Physics, Feynman derives the formula for gravitational potential energy by applying a line of reasoning he borrowed from Carnot on reversible weight lifting machines (FLP I, ...
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Comparing potential energy in non-relativistic classical physics and in special relativity
Preface
In classic physics the potential energy of a compressed (or stretched) spring is
$E_{\rm sp} = (\frac{1}{2})k_{\rm sp}(\Delta l)^2$
where $\Delta l$ is the length that the spring is compressed ...
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Work done by conservative and non-conservative forces
Work done by conservative forces changes one form of mechanical energy into another. Is it correct to assume that work done by non-conservative forces changes one form of energy to another, for e.g., ...
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Getting an opposite sign for the centrifugal potential energy in the effective potential [duplicate]
Consider a system whose Lagrangian is
$$L = \frac12 \mu\left( \dot r^2 + r^2 \dot\theta^2 \right) -U(r) $$
By the Euler-Lagrange equation,
$$\frac{\partial L}{\partial\theta}=\frac{d}{dt}\frac{\...
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Gravitational Potential Energy Lab Confusion
I had a lab that tested the dependence of gravitational potential energy on its position and the goal out of each exercise was to see if kinetic energy equaled potential energy. A cart was on a flat ...
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Intuition behind gravitational potential
Gravitational potential at a point is equal to work done in bringing a unit mass from infinity to a particular point
That was the text book definition
$$V_{p} = -\frac{GM}{r}$$
If we calculate $V_p$ ...
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How Can there be a Gravitational Potential when there is NO Gravitational Field? [closed]
How does it make any logic that there exist a potential when there is no net field
for example when we have a Hollow Sphere with mass we can find out the the gravitational *potential inside the sphere ...
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Comparing Electric Potential Energy of two Charges
I do not know what I am missing here and would appreciate a little help in figuring out the flaw in my logic. I have a row of positive charges and a row of negative charges as shown in the image above....
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Textbook question on calculation of potential difference between two points
My textbook has the following question
What is the potential difference between two points that are 50cm and 80cm respectively from a point charge of 2uC?
Unfortunately, the textbook has not taught ...
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In equation (3) from lecture 7 in Leonard Susskind’s ‘Classical Mechanics’, should the derivatives be partial?
Here are the equations. ($V$ represents a potential function and $p$ represents momentum.)
$$V(q_1,q_2) = V(aq_1 - bq_2)$$
$$\dot{p}_1 = -aV'(aq_1 - bq_2)$$
$$\dot{p}_2 = +bV'(aq_1 - bq_2)$$
Should ...
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Why is work done by force $+mgh$ in the situation of throwing something up?
If there is a particle at point A(at rest) and a force moves it to point B(Above point A vertically)(final velocity = 0 at this point), the work done by gravity is $-mgh$. This I understand as the ...
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Why potential energy is not considered in the internal energy of diatomic molecules?
In thermodynamics, I am taught that there are 5 degrees of freedom in diatomic molecules since there are 3 for translational and 2 for rotational. I interpret degrees of freedom as "ways you can ...
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How does gravitational potential energy work in a very large distance?
Consider a thought experiment (that I made when I was in high school) involving a universe with only two objects: a massive planet and a small asteroid. Initially, they are millions of light-years ...
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