All Questions
11
questions
1
vote
3
answers
75
views
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 ...
- 117
0
votes
1
answer
86
views
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
1
vote
1
answer
2k
views
How to simulate orbits?
I was trying to code a simulator of a solar system, but I cannot find out the orbit trajectory equation. I have simulated my orbits with perfect circles by using the $\cos \alpha$ and $\sin \alpha$, ...
- 1,525
0
votes
1
answer
170
views
What is rate of change of Earth's gravity (jerk, 3rd derivative of position)? [closed]
We know that gravity changes with height so there must exist a jerk. Could I know the method to find it. Does there exists jounce(4th derivative of position) for Earth's gravity?
- 33
2
votes
2
answers
293
views
What would a graph of distance between two gravitational objects vs time look like?
Lets say there are two objects in space that are attracted to each other, and are a distance r from each other. The gravitation force between the two objects is $$G\frac{Mm}{r^2}$$ As they accelerate, ...
- 59
0
votes
4
answers
1k
views
Acceleration due to gravity during its journey up and down
When we throw an object up into the air, ignoring air resistance, etc, we define acceleration to be -9.8 m/s^2. When it goes down after its journey up, like a parabola, do we define the acceleration ...
- 23
0
votes
1
answer
296
views
Path of an object in gravitational field [duplicate]
How do you prove that path of a satellite or a planet is a second degree curve? In other words, how do you prove Kepler's law which states that planets move in elliptical paths?
0
votes
3
answers
450
views
How does an object gain energy when it enters a potential field?
Conservation of energy says total change in energy is $0$.
Let's assume a small object is in outer space (maybe like a football).
It moves towards a planet (assume planet has no atmosphere for ...
2
votes
1
answer
1k
views
Free fall and terminal velocity
An object in free fall is defined as one that is moving solely under the influence of gravity.
So if an object has reached terminal velocity(force of gravity is cancelled out by upwards force of ...
- 104
0
votes
1
answer
80
views
Minimum Distance for "Speed of Light Approach"
I tried to calculate the minimum distance between a planet and a test mass for the mass to attain the speed of light on colliding with the planet's surface if it were released from rest at the initial ...
- 833
0
votes
3
answers
35k
views
When does acceleration due to gravity equal positive/negative? [closed]
For example a projectile is launched at an angle. What would $a$ in $y=vt +.5at^2$ be?
Let's say I choose up to be positive. How do you not confuse yourself whether to use positive or negative $a$?
- 13