All Questions
Tagged with newtonian-gravity free-body-diagram
137
questions
-2
votes
5
answers
105
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When an object is thrown towards the sky it starts to gain potential energy, why?
I didn't think so because when an object is thrown towards the sky it already has kinetic energy and it looses it's energy due to the gravitational force of the earth.
When the object looses all of it'...
- 6,112
0
votes
1
answer
80
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Where am I wrong in proving that force perpendicular to motion increases speed and kinetic energy? [closed]
Lets think of a helicopter flying at some height $h$. It throws a food packet to a person on the ground from air. Let's neglect the air drag.
The food packet is thrown only with some velocity $v_x$ in ...
- 207k
0
votes
2
answers
277
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Newton's 3rd law and normal force
There is something I hope you can help me understand...
According to my physics course, when I stand on the surface of earth, the normal force prevents me from "falling down" because it's ...
CommunityBot
- 1
1
vote
1
answer
48
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Drawing a free-body diagram for a body residing on Lagrange point $L_4$ and $L_5$
I am aware of the fact that Lagrange points $L_4$ and $L_5$ are stable equilibrium points however I cannot understand why they are equilibrium points in the first place.
Consider a Earth-Moon system ...
- 207k
-1
votes
2
answers
195
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How does gravity effect to aircraft in sky?
Aside aerodynamics and buoyancy, Is there a simple way to explain how gravity is negligible in flight paths using free falling body diagram? In a parabolic trajectory,we know that at max height, ...
7
votes
7
answers
3k
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How do objects reach terminal velocity?
I understand the basics of this principle: the force of gravity acting downward on an object becomes equal to the air resistance acting upward on the object because as the object speeds up, air ...
- 50.2k
0
votes
1
answer
56
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Why is hookes law not obeyed in vertical circular motion? [closed]
We know that $$T=-kx=-k(R-L)$$where $L$ is the natural length of string, so the tension force must be constant. but in vertical circular motion the tension force is not constant (via analysis of ...
- 207k
-4
votes
1
answer
64
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Find the acceleration of a block sliding down on an accelerating inclined place [closed]
I don't understand the solution provided in the image. Using Newton's second law for forces along the x-axis (parallel to the inclined plane), shouldn't the equation be $ma = mg\sin \theta+ mb\cos \...
- 207k
0
votes
1
answer
93
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Does Weighing machine measure normal force or gravity or both?
A weighing machine measures the normal force applied by an object.
However 2 forces act simultaneously on the machine ( normal and mg )
Under normal conditions (a=0) N=mg .
So this would mean that a ...
- 358k
0
votes
1
answer
39
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Air Friction Newton III
I have question to the Newton III Law and Air Friction.
At the free Fall of a Body there is an Air Friction, which is in oppopsite direction to the Gravitation Force. In my opinion the Body pushes to ...
- 4,399
0
votes
0
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69
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Dynamic equilibrium of planets
We can describe statical equilibrium ( forces, moments ) in a cuboid $$ \Sigma F_x=0,\Sigma F_y=0,\Sigma F_z=0~$$ In dynamics can we describe similar dynamic equilibrium within an inertial ...
- 1,032
2
votes
2
answers
46
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Is there any effect of gravity in a vertical nonlinear spring? [closed]
I know that for a linear vertical spring, the governing equation of motion written in the presence of gravity is the same as the one written in the absence of gravity. We can either undergo a ...
- 207k
0
votes
3
answers
799
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Why cannot we go in outer space with constant speed?
Sorry if this question is very childish for experts here. This was the question I had in school and years later it has resurfaced. I did some google search but getting the same equations of ...
- 11
1
vote
2
answers
252
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Chain hitting a scale
a standard problem in textbooks is to calculate the force of a chain of length $L$ as it hits a scale and has fallen a length $x$. It is found to be $3gMx/L$ by the gravitational force $xmg/L$ and ...
- 36.1k
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4
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How can one say that an object is at rest when there is a constant acceleration $g$ acting on it?
A stationary object in a gravitational field, or a stationary charged particle in an electric field, has potential energy. If there is a constant acceleration, following this logic, how can I be at ...
- 1,064