All Questions
Tagged with potential-energy energy
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How is potential energy incorporated into mass in special relativity? [duplicate]
I've seen it said before that we often ignore potential energy in relativity because it can be included in the mass term. It is commonly said that a hydrogen atom has less mass than the sum of its ...
- 180
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I am confused about potential energy and work done by a force [closed]
Potential energy is the energy contained in a body due to its position. But I don't understand it because when object falls, PE= mgh and work done by gravity, is - mgh. So what is the difference other ...
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Paradox? Why does energy conservation appear to be violated in this simple geared system?
While answering a question about gears and levers, I found I could not get the work in to equal the work out in this simple gear system illustrated below:
The gears are set up to replicate a lever, ...
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Question about Problem $12$ in Chapter $11$ from Kibble & Berkshire's book
I write again the problem for convinience:
A rigid rod of length $2a$ is suspended by two light, inextensible strings of length $l$ joining its ends to supports also a distance $2a$ apart and level ...
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Where did potential energy disappear in this case?
Just a new thought experiment. We know that the kinetic energy depends on frame of reference as do work and velocity. Now we can consider a falling ball. It converts potential energy to kinetic energy ...
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Shape of graph of energy in S.H.M
I'm confused to whether the graph of KE/PE of a simple harmonic motion system is sinusoidal or not
those are my best sketches but if unclear, the blue one is in a shape of a sine wave.
this question ...
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Question related to conservation of energy
Here is a textbook passage that I have trouble understanding. It is taken from Classical Mechanics by Tom WB Kibble and Frank H Berkshire.
We consider first a particle moving along a line, under a ...
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If a 100,000 ton container ship slams into a bridge at 8.6 knots how much energy was moved into the pylon and at what rate of transfer speed? [closed]
Edit: the entire question is in the title, the answer should be an amount of energy and a value of energy transfer in some unit, but not knowing enough about physics I don’t know what the appropriate ...
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Energy in different coordinates in central force motion
With reference to central force, we see that K.E has 2 terms in 2D cartesian cordinate but just 1 term in polar coordinates and potential energy has 1 term in cartesian but 2 terms in polar.
Basically ...
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Does mechanical energy means total energy?
I know that mechanical energy is the sum of kinetic energy and potential energy. But there is a sentence in the book like this:
'Our primary goal, however, is to find the energies associated with ...
- 107
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Energy in electric field of an electron?
I am just trying to get an intuition for the Griffiths equation no. 2.45, where work done to establish a field E is given by
Say we want to solve it for electric field due to an electron (point-charge)...
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Why does the total gravitational potential in the universe exactly equal the total mass energy RIGHT NOW? [duplicate]
In the zero energy universe model, the gravitational field has negative energy, and this negative gravitational energy of all the distant mass exactly balances and cancels the positive mass-energy in ...
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Change in Work-Energy Theorem
We have Work-Energy Theorem as follows:
$$W_c +W_{nc} + W_{ext} = ΔK$$ $-(1)$
, where $W_c$ = work done by conservative forces,
$W_{nc}$ = work done by non-conservative forces, $W_{ext}$ = work done ...
- 349
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When is the internal energy of a system not considered potential energy? [duplicate]
I have seen the total energy of a system, $E$, given in two forms:
$$E = K + U$$
where $K$ is the kinetic energy and $U$ is the potential energy, as well as
$$E = K + U + I$$
where $I$ is the internal ...
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Work and Energy Theorem - Theoretical Question
The work energy theorem states that for a given object
∆ Kinetic Energy = Work done by all forces ( Conservative, Non Conservative, External )
Here ,
Suppose if ∆KE = 0 , Potential energy has changed
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