All Questions
Tagged with newtonian-gravity kinematics
72
questions
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3
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75
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How much time does it take for an object to fall from space? [closed]
Let's say there's an object of mass $m$ in space, $h$ meters away from the surface of the Earth. $h$ is large enough that $g$ cannot be assumed to be constant. The acceleration varies according to ...
- 119
0
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2
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68
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Minimum initial velocity to avoid collision [closed]
I'm having problem with the solution of this question:
Two material points with mass $m$ move along a horizontal axis subjected only to Newton's gravitational force law. At the instant $t_0=0$, one ...
- 237
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1
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105
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Differential equation of an object dropped from certain height
I want to solve this problem -
A ball of mass 2kg is dropped from a tall building with zero initial velocity. In addition to gravity, the ball experience a damping force of the form -2v, where v is ...
- 333
3
votes
5
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183
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What happens physically when object is thrown up when $v$ becomes 0 at max height?
When velocity=0 during maximum height when an object is thrown up, what does that actually mean?? does that actually mean that the object doesn't change it's position over dt time period when at ...
- 31
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1
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329
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Is friction equal to gravitational force during rolling down a ramp?
I'm studying the motion and forces involved in a ball (bidimensional) rolling down a ramp inclined by an angle $\theta$ from the x-axis.
This is the body diagram (I didn't draw forces but there is ...
- 3
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86
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An object falling from very far would have varying acceleration, how can that be accounted for?
I want to have a function that describes where a falling object is.
Like this one:
h(t) = -g*t²/2
But this one is for the usual close to the surface case, where there is no variation of gravity due to ...
- 101
17
votes
14
answers
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Why do rain drops fall with a constant velocity?
While reading my physics book. I came across a line that says that:
Rain drop falls with a constant velocity because the weight(which is the force of gravity acting on body) of the drop is balanced ...
user315348
0
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2
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271
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Time to hit ground after dropping object [closed]
I have an object that is 9 meters above the surface of the earth, in vacuum. If I drop it I'm trying to figure out how long it will take to reach the ground. My teacher gave me the formula below, I'...
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3
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224
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Equation of motion of a classic inverted pendulum in free fall
I was thinking in this interesting problem:
Suppose we have this inverted pendulum:
But without this control force $F$ and the system would by loose from a height $h_0$, with initial velocity $0$ ...
2
votes
2
answers
387
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Importance of Acceleration in Newtonian Physics [closed]
I'm a just a hobby enthusiast in physics.
Why is acceleration important and what are the major things we would miss if we are unaware of this quantity in terms of Newtonian physics?
Like what would to ...
- 61
1
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1
answer
82
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Exact distance travelled by an object due to gravity only
I am aware of the fact that for two point masses in space, the time that it will take for them to collide is, T=$\pi \sqrt{\frac{r_i^3}{8GM}}$, where M is the sum of the 2 bodies' masses, $r_i$ is the ...
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What will happen to the ball in a vacuum container when suddenly the gravity after 2 seconds disappears? [closed]
Suppose that there is a ball in a vacuum container where mass of the ball is $2$ kg. The height of the container is $100$ m. Assume that the acceleration due to gravity is $10$ m per second square.
I ...
- 17
0
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5
answers
123
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Vertical motion under gravity
If we project an object vertically under gravity it travels vertically upwards until vertical velocity zero, why is that? Why does the velocity become zero?
- 21
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2
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What would happen if you stand on a platform that can just support your weight and jump up?
I have played many video games and the title summarizes a scenario I have encountered many times, mainly platformers.
So in this scenario, the platform in question is structurally weak, be it ice, ...
user279395
-2
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2
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154
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Why does the size of the ball change?
I am reading Head First Physics.
On page 372 it states that the size of the ball changes. I have checked my previous notes, but I cannot understand why?
Here is a picture of the page:
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