All Questions
Tagged with definition forces
180
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What is a conservative force?
Currently I have three different pictures to describe/understand conservative forces.
For the moment I just want to get an electron from point A to point B. In the near surrounding is another electron ...
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1
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Derivation of formula of potential energy by a conservative force [duplicate]
the formula for potential energy by a conservative force is given by:
$$ F = -\nabla U(r), $$
which in one dimension may be simplified to:
$$ F = -\frac{dU}{dx} .$$
My question is how is it ...
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4
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The physical definition of work seems paradoxical [duplicate]
So this is possibly a misunderstanding of the meaning of work, but all the Physics texts, sites, and wiki that I've read don't clear this up for me:
In the simplest case with the simplest statement, ...
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Does the displacement in the definition of work correspond to the displacement of the object or the point of application of the force?
Work is defined as
$$W = \vec{F}\cdot\vec{s}$$
But what what exactly is $\vec{s}$? Is it the displacement of the body on which the force is being applied? Or is it the displacement of the point of ...
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What does Feynman mean when he says that $F=ma$ is not exact?
Chapter 12-2 in Feynman Lectures Vol. 1 states:
In fact the law, $F=ma$ is not exactly true; if it were a definition we should have to say that it is always true; but it is not ...
First, because ...
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Exactly how much lift is needed to overcome the weight of an average person?
I am designing a "glider" of sorts, and I have some basic questions about the physics involved to get me started. How much lift is required to overcome the weight of an average person, say 150 pounds? ...
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Does a force do work on an object with constant velocity?
I know that a force does no work on an object if the object's displacement is zero, but if an object is moving at a constant velocity $\bar{v}$, and a force $\bar f$ (let's say that $\bar f$ and $\bar ...
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Why is the mechanical advantage of a wedge = length of slope/ width?
Mechanical advantage is defined as Force Output/Force Input
For a symmetrical wedge with the length of the slopes being equal and the width being the distance between the end points, the articles ...
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2
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Is there a definition of force? [duplicate]
Well, Newton's three laws talks about forces, but no definition is given. In truth, Newton's second law gives an idea of what total force is: the time change rate of momentum. But, if we have a force ...
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Are Newton's "laws" of motion laws or definitions of force and mass?
If you consider them as laws, then there must be independent definitions of force and mass but I don't think there's such definitions.
If you consider them as definitions, then why are they still ...
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Clarification regarding Newton's Third Law of Motion and why movement is possible [duplicate]
Newton's third law states that to every action, there is an equal and opposite reaction.
If that's the case, then how do things move at all? Shouldn't all applied forces be canceled by the equal and ...
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How would you determine whether an object is at equilibrium? [closed]
How would you determine whether an object is at equilibrium or not?
What is the definition of equilibrium?
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Define Pressure at A point. Why is it a Scalar?
I have a final exam tomorrow for fluid mechanics and I was just looking over the practice exam questions. They do not provide solutions. But pretty much I have to define pressure at a point and also ...
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History of interpretation of Newton's first law
Nowadays it seems to be popular among physics educators to present Newton's first law as a definition of inertial frames and/or a statement that such frames exist. This is clearly a modern overlay. ...
user4552
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What exactly is $F$ in $W = \int_{a}^{b} F dx$?
I am trying to teach myself some basic physics, here is something I do not really understand about the definition of work:
When moving from $a$ to $b$ (in one dimension), the work done is defined to ...
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