All Questions
Tagged with homework-and-exercises potential-energy
395
questions
0
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3
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196
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I know that electric potential energy is defined for a system of charges, not for a single charge. But what about electric potential?
My professor explained me in the best manner possible about the electric potential energy and why it is NOT defined for a single charge, BUT my question is as Electric potential is just electric ...
- 23
4
votes
3
answers
250
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Why is my answer for height negative?
Question is simple. A ball is thrown upwards with initial velocity $v_0$. How high does it go up?
Assume down is negative and up is positive and no air resistance.
KE at bottom = PE at the top:
$\...
- 109
0
votes
1
answer
106
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Change in potential and kinetic energy after a photon is absorbed by a electron
This is a question from the AP Physics 2 2022 FRQ. Why does the potential energy of the atom and the kinetic energy of the electron decrease after a photon is absorbed? Shouldn't both of them increase?...
- 3
0
votes
1
answer
23
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Finding the spring constant and magnitude of acceleration when it is dropped with the top attached to a ceiling [closed]
I've tried finding the potential energy by using PE = mgh then using PE = 1/2kx^2 to find k and setting PE = KE to find PE using velocity but neither is correct when finding the spring constant. I don'...
- 3
0
votes
1
answer
86
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Schrödinger-Propagator for combined linear and harmonic potential
Given the Hamiltonian
\begin{equation}
H = \frac{p^2}{2m} + V(x)
\end{equation}
The propagator for a pure harmonic potential of the form
\begin{equation}
V(x) = \frac{1}{2} m \omega^2 x^2
\end{...
- 141
1
vote
1
answer
26
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Right displacement in spring potential energy [closed]
I have a doubt in general, the above problem is an example.
Here , the elastic string can be treated as a spring and we know the potential energy of a spring is $\frac{1}{2} k (x_f-x_i)^2$
So , ...
- 11
0
votes
3
answers
67
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How do velocities become equal when potential energy is maximum? [closed]
I was given this diagram and asked to find the maximum potential energy during the subsequent motion if one of the blocks is projected with a kinetic energy K initially.
So I did reach upon the answer ...
- 23
0
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1
answer
24
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Restriction to a region of potential energy [closed]
A particle with total energy E is moving in a potential energy region U(x). Motion of the particle is restricted to the region when?
(A) U(x) > E.
(B) U(x) < E.
(C) U(x) = 0.
(D) U(x) ≤ E.
I ...
-1
votes
1
answer
135
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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 ...
- 1,421
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2
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524
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Gravitational potential energy of an object on Earth compared to Moon
The gravitational potential energy of a $200\,\text{kg}$ satellite $3000\,\text{km}$ above the surface of the Earth is $U=-\frac{GMm}{r}=-8.5 \times 10^9\,\text{J}$.
Would the gravitational potential ...
- 372
0
votes
1
answer
440
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Finite potential well and nature of its solutions
The question I have is about nature of solutions, not a solution or a specific answer that I am looking for. If we define a potential well centred at $x=0$ as the following,
$$V(x) = \left\{ \begin{...
- 131
5
votes
1
answer
114
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Insecurity about introductory classical mechanics [closed]
This is a problem I encountered, but not a homework assignment, I'm not only just looking for solutions here... This is my first time encountering questions like this, I'm sure you remember the first ...
- 287
0
votes
1
answer
49
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How do I visualize total potential energy of charges?
In the following exercise from University Physics with Modern Physics (Young, Hugh D.; Freedman, Roger A..)
Two point charges are at fixed positions on the $x$-axis, $q_1 = -e$ at $x = 0$ and $q_2 = ...
- 1
0
votes
2
answers
50
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Orientation of gravity force in energy [closed]
My apologies in advance if this is a stupid question.
A 0.20 kg rocket in a fireworks display is launched from rest and follows an erratic flight path
to reach the point P, which is 29 meters above ...
- 179
1
vote
1
answer
62
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Two charged spheres connected by a wire and one is inside the other [closed]
Two charged spheres are connected by a wire, a small sphere is located inside a bigger one. Both spheres are charged and connected through a wire. The charge of the small sphere is 20µc and the charge ...
- 11