All Questions
Tagged with gravity newtonian-mechanics
317
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Minimum mass of asteroid that could knock moon away [closed]
What is theoretically the minimum mass of asteroid, coming from deep space, that could knock the Moon away from Earth? The asteroid is not hitting the Moon, just interacting with it by gravity.
I was ...
1
vote
2
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614
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Mass hanging from vertical spring
Why does a mass hanging from an ideal spring, under gravity, undergo periodic oscillations? Isn't gravity a damping force here? Equation for mass spring system is given by $m\ddot{y}+ky=0$ where ...
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1
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648
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Newton's first law - elevator lift upward and downward force [duplicate]
Why does $F_c$ is equal to $F_g$ and why $F_c$ isn't greater than $F_g$? $F_c$ is moving it upward right, so the force must be greater than gravity to pull it upwards I think.
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How could inertial and gravitational mass be even conceptually different?
From https://en.wikipedia.org/wiki/Mass
Although inertial mass, passive gravitational mass and active gravitational mass are conceptually distinct, no experiment has ever unambiguously demonstrated ...
- 105
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3
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165
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Problem with Action-Reaction pairs and gravity [duplicate]
There are lot of question on this site similar to this, but they give contradicting opinions.
When standing on earth, my gravitational pull to the earth and earth's gravitational pull towards me ...
0
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2
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174
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A falling particle on a "roller coaster"
Suppose a particle is sliding down the hill only because of gravity. But then the hill smoothly flattens out and the particle has to pass a circular loop and must not fall off the loop at any instant ...
- 105
1
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1
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123
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The behaviour of acceleration of a ball in motion
I have a few doubts on how the acceleration of a ball works when we throw it up in the air, In my mind, I could imagine it in some different "real world" cases, So I am listing them all down,...
- 209
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58
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Gravitational force acting on a small element on a sphere
I was given a formula that force acting on a small element on a sphere (made by connecting two hemispheres) to the center of the sphere equals:
$$dF = \frac12 \cdot G\cdot m\cdot dm/r^2$$ I cannot ...
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71
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The gravitational potential at the center of a solid ball (confusion)
I came across this question during my physics class. Suppose we have a solid, spherical planet with mass $M$ radius $R$ s.t. the density of this planet is uniform everywhere, then what is the ...
- 115
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2
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145
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Why does a system with zero resultant moment turn after temporarily force-tilted?
Say a beam, 3m long from end to end, has a pivot placed at its centre of mass, at half its length i.e. 1.5m. Objects with weight 200N each are placed on both ends of the beam. The system is in ...
- 340
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542
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State space of free falling object is time variant?
In the case of a free fall object, if $h$ denotes distance from floor and $v$ the speed, then, given an input $U = g$, and $X=[h \quad v]^T$ and $\dot{X}=[\dot{h} \quad \dot{v}]^T$, I found that the ...
0
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2
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2k
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What balances out the Normal force in this scenario of uniform circular motion?
In my Physics course we are dealing with uniform circular motion. In this scenario there is an object in horizontal uniform circular motion.
In the FBD provided in the problem the gravitational force ...
- 137
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100
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If I throw an object upward will its acceleration change or it will stay constant at $-g$?
I mean if, for example, I throw a rock upward, its acceleration will always be $-g$ or it will be $-g+a$ because I apply a force on the object when I throw it? (without considering friction)
3
votes
1
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89
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At what height should I drop my kids from to prevent getting splashed? [duplicate]
Today as I was performing my morning biological ritual, "dropping the kids off at the pool" and what not, the cold kiss of Poseidon on my behind inspired an idea for an experiment. What is ...
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4
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3k
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Ball thrown faster than terminal velocity [duplicate]
I recently read about the property of terminal velocity for objects and I got a question when doing so.
If from a very tall building I throw a ball faster than terminal velocity downwards, will the ...
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