All Questions
Tagged with definition forces
180
questions
6
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Are Newton's laws just definitions?
I have read a bunch of articles online regarding my question but none have helped.
Newton's Laws:
In an inertial reference frame, an object's momentum doesn't change unless the object is acted upon ...
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4
answers
163
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What does the $F$ in Newton's second law equation mean?
This is a super simple question: does $F$ represent the net force exerted on an object or the force it exerts on another object as a result of momentum? Say a ball is rolling. In this specific ...
- 51.4k
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4
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What are internal and external forces?
what is internal and external force? How do I decide what forces are internal and external?
in work-energy theorem and conservation of mechanical energy, do we consider internal, external, or both ...
- 56.4k
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1
answer
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What is the difference between the applied, external force and the generalized force?
in analytical mechanics, we define the generalized force using the applied force times $dr/dq$. If I want to express the difference between the external and generalized force in words in order to ...
CommunityBot
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5
answers
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Why is torque defined as $\vec{r} \times F$?
Here I cannot convince myself myself that it is units because the torque is defined to be in units of Newton meter is a reiteration of the law stated above. Why was it not $r^2 \times F$ or $r^3 \...
- 13.1k
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How exactly IS Newton’s second law verified experimentally?
In R. Shankar’s “Fundamentals of Physics : Vol 1” while discussing Newton’s Second Law of Motion, Prof. Shankar raises the question : how do we know Newton is right? I quote from the book :
Take ...
CommunityBot
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4
votes
3
answers
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Why isn't work a state function?
I've heard the example, that work is path dependent. But whether I climb a mountain directly or in serpentines, in the end it's the same amount of work, with the one difference that it takes me longer ...
- 21.9k
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2
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In physics, what is the difference between a fact and a definition?
For example, I came across this statement:
"It is a fact that the components of force are derivatives of potential energy, but it is not a definition."
What does this statement mean?
I ...
- 4,399
2
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1
answer
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Definition of generalized force in Lagrangian formalism
In some texts (e.g. Taylor's Classical Mechanics), the generalized force is defined to be (I'll simplify to one particle in one dimension for ease of notation): $Q \equiv \frac{\partial{L}}{\partial{q}...
- 207k
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3
answers
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Work done on a frictionless surface
Imagine that we apply a force $F$ on a frictionless surface to move a body by a distance $d$. (The body starts at rest and is stopped after moving a distance $d$.)
Is the work done $F d$?
But from ...
- 6,102
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What exactly is force - apart from "the ability to do work"? [duplicate]
Does force - any kind - have an identity of its own apart from the set of effects it brings about? Or is it just "that which" ... "causes"; does this and that, makes certain ...
- 207k
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2
answers
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Difference between moment and couple
What is the exact difference between a moment and a couple? In some YouTube channels and books, they say the moment of a force produces a translational as well as rotational motion whereas the concept ...
- 107
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4
answers
381
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How is the definition of work motivated?
For most dynamical variables in classical physics, I can understand how one may have decided to introduce them as a result of some "incompleteness" in Newton's laws of motion. For example:
...
- 134
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2
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175
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What is normal force and when it acts?
what are contact forces and according to: https://www.physicsclassroom.com/class/newtlaws/Lesson-2/Types-of-Forces
it says there are 6 types of contact forces. I am having doubt with applied force and ...
- 207k
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1
answer
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What is difference between normal force and reaction force? [duplicate]
according to my book the perpendicular component of reaction force is called normal force when there is contact between two bodies. I can not understand that how for example when we jump we pushes the ...
- 207k