All Questions
Tagged with potential-energy energy
69
questions
1
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2
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11k
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Work done relation to potential energy
I know work done is negative of change in potential energy, I.e., $W=-(∆U)$.
It means that Work done against a force (or work done on a system) increases its potential energy.
And Work done by a ...
- 356
1
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3
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2k
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Work kinetic energy theorem
I don't understand the wordings of this theorem. Can someone please help me in understanding this? Secondly, on what basis are the sign conventions in this theorem applied? I get confused in positive ...
- 39
0
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2
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296
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Sign in $\Delta U= -\int\vec{F}\cdot d\vec{l}$
So I have been trying to understand why there is a negative sign in the following$\Delta U= -\int\vec{F}\cdot d\vec{l}$
I wanted to try to understand it by trying to derive the gravitational ...
- 157
16
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3
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6k
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Do all forms of energy fall under kinetic and potential energy?
I know that energy is recognized through motion. Even in the mass-energy equivalence a velocity is present even though it is a rest-energy (Not really sure if this would count as a potential energy ...
- 551
15
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2
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5k
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How is energy stored in magnetic and electric fields?
We say that there is energy associated with electric and magnetic fields. For example, in the case of an inductor, we give a vague answer saying that an energy of $\frac{1}{2} LI^2$ is stored in the ...
- 7,203
14
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5
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Does potential energy of an object increases its relativistic mass?
I know that in relativistic condition the increase in kinetic energy of an object increases its relativistic mass as $$m=\frac{m_0}{(1-v^2/c^2)^{1/2}},$$ and mass is another form of energy.
So my ...
- 141
12
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3
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How does one prove that Energy = Voltage x Charge?
We know
$$E = q V$$
where $E$ is the energy (in Joules), $V$ is the potential difference (in Volts), and $q$ is the charge. Why is this equation true and how we prove it?
- 829
9
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What can be known about the formulas for energy only from the fact that it is conserved?
The question is to figure out how the energy can be derived knowing just one thing:
There is a quantity called Energy that is conserved over time.
The goal is to get an equation that somehow ...
- 1,760
6
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1
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2k
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What is the correct expression for the magnetic energy density inside matter?
I'll use a magnetized sphere as an example, of radius $R$, with a magnetization density $\vec{M}$. The magnetic moment of the sphere is $\vec{\mu} = \vec{M} \, V$. The magnetic field inside and ...
- 7,592
5
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13
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4k
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Energy transfer during perfectly elastic collision between bodies of same mass
My question is similar to this one but it is for sure not a duplicate of it. I basically want to see the same scenario in terms of energy transfer.
What I know for sure is that bodies under collision ...
- 8,220
4
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3
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5k
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Where is the potential energy due to internal interactions in total energy?
In thermodynamics the total energy of a system consists of kinetic energy of motion of the system as a whole, potential energy of the system as a whole due to external force fields, and energy ...
- 1,810
4
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2
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9k
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Can magnitude be negative?
My teacher told that magnitude is the positive value of that quantity or the modulus of that quantity.
he also told that vector quantities have both magnitude and direction and scalar quantities have ...
- 592
4
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7
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6k
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Why does positive work done by internal conservative forces $\implies$ decrease of potential energy?
Potential energy can be thought as the amount of work that the force can potentially do on the point because of its position. $$W=-\Delta U=U_{initial}-U_{final}$$
A positive work done by a force ...
- 2,617
4
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3
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534
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Energy contributions of Hamiltonian density
In Lancaster and Blundell, Quantum Field Theory for the Gifted Amateur, p.99, the Hamiltonian density is
\begin{equation}
\mathcal{H}=\frac{1}{2}[\partial_0\phi(x)]^2+\frac{1}{2}[\nabla\phi(x)]^2+\...
- 497
3
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2
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130
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Does electron-proton interaction and electron-electron interaction in an atom gives rise to a microscopic potential energy?
When studying thermodynamics we come across a property of a system called internal energy, which is the sum of all energies possessed by the system at the microscopic level. Internal energy has two ...
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