Questions tagged [work]
The product of the force on an object and the displacement the object undergoes along the direction of the force.
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Weird integral notation for work
As part of a thermodynamics class my professors had a weird intergral. Let $\vec F$ be a force acting on a piston. $\vec F = -p A \vec{e_x}$. Since work is $W_{12}= - \int^2_1 \vec F \cdot \vec {dx}$.
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Is the electric field a conservative field? [closed]
Assertion: Work done in moving a charge around a closed path in an electric field is always zero.
Reason: Electrostatic force is a conservative force.
Answer:
We know that the work done by the ...
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Derivation of $W = -\int_0^{B_a} \mathbf{M} \cdot d\mathbf{B}_a$ work done moving a superconductor into a magnetic field
I am studying Kittel's Solid State Physics chapter 10 on Superconductivity.
On page 271, Kittel states the work done per unit volume on a superconductor by moving it at a constant temperature from ...
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Confusion regarding variable value of external work done [closed]
So I was thinking about work done in different frames of references, when I came across the following example.
Consider a rod of mass $m$ and length $l$, hinged at one end and free to rotate in the ...
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Center of mass acceleration through forces applied at other points
Until recently, I thought that the only way to cause transitional acceleration is to apply a force at the center of mass and forces applied anywhere else would only cause rotation. I believe I was ...
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The Orthogonality Paradox: Why the Work-Energy Theorem ($W=0$) forbids Tangential Acceleration in Radial Force Systems? [duplicate]
In classical mechanics, the reduction of an orbital radius (e.g., a tethered mass) is typically governed by Conservation of Angular Momentum ($L = mvr$), which predicts a significant increase in ...
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If an object is moving in a constant velocity how can work be done? Do the individual forces do work?
Suppose, an object is already moving with constant velocity. Now two forces of equal magnitude and opposite direction act on it, so the net force is zero and the velocity remains constant.
Now,
Is ...
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Kinetic Energy expression for variable mass system
An object is created by assembling mass (initially at rest) as per the equation $m(t)=\frac{Mt}{T}$. The mass being assembled is experiencing an external force that increases the velocity of the mass (...
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What is the origin of the Kinetic Energy formula $(1/2)mv^2$? [duplicate]
Forgive me because this is a very elementary question, but was the formula for Kinetic Energy ie. $(1/2)mv^2$ derived using the Work Energy theorem? How did the understanding of "energy" as ...
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Why is the potential energy of an element in a string not a negative value?
I am learning about energy in wave motion, specifically about the energy of waves travelling in a string. My textbook gave the equation for th potential energy as
$$ dU = T(dl - dx). $$
It states that ...
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Am I correct in my understanding of how the reverse Carnot Cycle works? [duplicate]
So, when the gas (initially at the heater temperature T1) is compressed isothermally, it does not come into contact with the cooler, and in order to prevent the gas temperature from exceeding the ...
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Why the reverse Carnot Cycle works?
I don't understand why the reverse Carnot Cycle works. Let's consider the isothermal expansion of a gas (body). The gas does work, but its temperature remains constant. For this to happen, the gas ...
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Where is the increased mass accumulated based on Einstein's mass-energy equation?
Assume a huge parallel-plate capacitor with plates located at an infinite distance away from each other. If we tend to move a positively charged object ($+q$) with a rest mass of $m$ against the ...
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How could one show that kinetic friction is a non-conservative force?
The question is not to talk about why kinetic friction is non-conservative, but rather if there is a way that I could show mathematically that the work done by kinetic friction is path-dependent?
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Does the electric potential energy of a positively-charged particle vary directly with its distance from a charged particle or surface?
Current high school AP Physics II student here, so apologies if this question comes off as unlearned.
I'm trying to learn about electric potential in my class, but I realize I still don't understand ...
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