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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What is meant by potential energy for a particle in a field?
Potential energy is usually defined using a field and a particle that experiences the field force, as the work down in moving a unit particle from infinity to a position in that field.
But some ...
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Could someone remind me what this means again? $\nabla U = \pm F$
You know that for a potential function (conservative force/fields) that
$\nabla U = \pm \vec{F}$
In math, we don't have that minus sign, we have only the plus one.
What does it mean if you get rid ...
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Electron volt and Voltage
Voltage is the work done per unit charge. Given by:
V = W/q
Electron volt is the maximum kinetic energy gained by the electron in falling through a potential difference of 1 volt. Given by:
K.E (...
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Meaning of subscript in $V=\frac{1}{2}\left(\frac{d^2 V}{{dq_i}{dq_j}}\right)_0$
This is probably a simple question, but what does the subscript $0$ mean in the following expression?
$$V=\frac{1}{2}\left(\frac{d^2 V}{{dq_i}{dq_j}}\right)_0$$
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Higher To Lower Electric Potential
The question I am working on is:
"An electron moving parallel to the x axis has an initial speed of $4.65 \cdot 10^6~m/s$ at the origin. Its speed is reduced to $1.27 \cdot 10^5 ~m/s$ at the ...
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Potential energy of a spring
I'm puzzled about the potential energy of a spring. A spring is a conservative system. So the potential energy should be defined only up to a constant -- can be defined to be 0 anywhere. However, ...
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Direction of rotation of proton in magnetic field--opposite to a dipole
Chatroom created by @pcr for discussing this: http://chat.stackexchange.com/rooms/2824/direction-of-rotation-of-proton-in-magnetic-field
Here's a small paradoxical question I was asked a long time ...
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How much (usable) potential energy is stored in a compound bow?
I have done a bit of reading about the energy stored in bows, but I haven't seen anywhere a description of how much energy actually is stored. Clearly there are many factors, bow design being ...
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Why is the spring constant $W_p''(0)$?
According to my physics book, the spring constant can be calculated from knowing the potential energy, with the formula $k = W_p''(0)$.
I don't really understand why, and the book doesn't explain it ...
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exercise concerning the inclined plane
I have an exercise to ask yourself.
A ball of mass m = 5 g starts at rest and travels 50 cm along a ramp
inclined at 45 ° to the horizontal. a) If we imagine frictionless motion
of the ball along the ...
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Elastic potential
I have a doubt:
elastic potential energy is given by: $U=\frac{k}{2}x^2+K$
but does elastic potential exist? (for example: potential gravitational energy is given by $U=mgz+K$ and gravitational ...
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Derivation of the self gravitational potential energy of a sphere
I have been searching on the Internet but have not found a derivation of the formula for the self gravitational potential energy of a sphere. Can someone show how to do this? I assume it involved 6 ...
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Is there a mathematical derivation of potential energy that is *not* rooted in the conservation of energy?
For simplicity I'll consider only gravity, but in general this question only applies to conservative forces.
As per my understanding, the way one gets to the equation for gravitational potential ...
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Is more energy required to magnetize based on its distance to other objects?
I have had this question since I was in college physics, but never could figure out how to express it. Well, now I think I have it.
Let's imagine two scenarios A and B. Both scenarios start with two ...
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Do field and potential energy always come together?
Is energy directly due to a field always potential energy?
Is potential energy always due to a field?
From the two Wikipedia links:
a field is a physical quantity that has a value for each point ...
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