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0 votes
1 answer
36 views

Drawbacks of Quasi-Static process for lifting a block

Definition of Quasi-static: A quasi-static process is a thermodynamic or mechanical process that occurs very slowly, allowing the system to remain in a state of equilibrium at all times. While ...
Akhilesh G's user avatar
-1 votes
2 answers
76 views

When is minimum potential energy in simple harmonic motion not zero?

We know that in simple harmonic motion, potential energy is minimum at the mean position and it is zero since displacement is zero. So what are some cases in which minimum potential energy is not zero?...
android's user avatar
  • 91
0 votes
0 answers
30 views

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 ...
Aidan Beecher's user avatar
1 vote
2 answers
53 views

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 ...
android's user avatar
  • 91
0 votes
2 answers
113 views

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, ...
KDP's user avatar
  • 6,102
0 votes
1 answer
58 views

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 ...
panos Physics's user avatar
0 votes
2 answers
41 views

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 ...
Hazim Ahmed's user avatar
-1 votes
2 answers
59 views

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 ...
Safa yousif's user avatar
0 votes
2 answers
76 views

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 ...
Hazim Ahmed's user avatar
-6 votes
1 answer
163 views

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 ...
MetaGuru's user avatar
  • 105
0 votes
2 answers
74 views

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 ...
SHINU_MADE's user avatar
0 votes
2 answers
82 views

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 ...
KHJ's user avatar
  • 107
4 votes
0 answers
58 views

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)...
SACHLEEN SINGH's user avatar
0 votes
1 answer
69 views

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 ...
Miss Understands's user avatar
0 votes
0 answers
35 views

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 ...
PinkAura's user avatar
  • 349

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