The free-fall tag has no wiki summary.
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0answers
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not all items fall at the same rate some items have outside facters gain speed in which they “fall” [closed]
I was reading one of the post this morning and found it fasanating with all the formulas that were being poured out about items will falling at the same rate given the same hight that they were droped ...
3
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4answers
2k views
Calculating impact force for a falling object?
Good evening, I'm trying to calculate what kind of impact force a falling object would have once it hit something. This is my attempt so far:
Because $x= \frac{1}{2} at^2$, $t=\sqrt{2x/a}$
$v=at$, ...
25
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6answers
1k views
Can I survive a free fall using a ramp and a rope?
Can I survive a free fall by carrying a very light and resistant ramp using a rope?
Note: lets assume the ramp is a little bit heavier at the bottom and I am very skilled at making it always land ...
0
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1answer
93 views
Surviving Free Fall with the Help of Mr. Bernoulli
What is the best strategy to survive a free fall naked out of a jetliner at cruising altitude (ignoring temperature)?
For instance, my strategy would be to streamline my fall so that my terminal ...
3
votes
1answer
197 views
Wave pulse on a freely falling rope
Consider a rope hanging from the ceiling (massive / massless irrelevant, I suppose). A wave pulse is set up on the rope. Just as the wave pulse starts propagating on this rope, the top of the rope is ...
1
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2answers
156 views
Should the cold drink come out of a free falling bottle with an open lid?
If I hold an open bottle and perform free fall, say sky diving, along with it from, say 10000ft, while I'm holding the bottle vertically upwards should the cold drink come out of the bottle? Kindly ...
3
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1answer
87 views
How deep is the well, given this data?
A rock is dropped into a well. A timer starts when the rock is dropped and is stopped when the noise of the rock hitting the ground of the well is heard. How deep is the well?
Here's what I have so ...
2
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1answer
323 views
Does the metal foam “whiffleball” orbital reentry idea make any sense?
Planetary Resources is a company speaking publicly about mining near Earth asteroids for resources. I'm interested the physicality of a claim they make in a video here:
...
1
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1answer
193 views
Gravity and free fall
In Wikipedia it's stated that "[..] gravity, is the natural phenomenon by which physical bodies appear to attract each other with a force proportional to their masses".
Then I found many examples ...
42
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9answers
7k views
Don't heavier objects actually fall faster because they exert their own gravity?
The common understanding is that, setting air resistance aside, all objects dropped to Earth fall at the same rate. This is often demonstrated through the thought experiment of cutting a large object ...
26
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6answers
22k views
Could someone jump from the international space station and live?
Felix Baumgartner just completed his breathtaking free-fall skydiving jump from $120,000\,\text{feet} = 39\,\text{km}$ above the Earth, breaking the speed of sound during the process.
I was wondering ...
3
votes
2answers
230 views
Consequences of destroying a space elevator
Suppose there is a fully functional space elevator built on Earth. The base is attached to coordinates
$
(\lambda, \varphi) = (0,0)
$
e.g., on the equator on the zero-meridian.
What would happen ...
0
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0answers
59 views
Using thermodynamics and Kinematics together to solve a parachuter problem?
I need to find a parachutist's displacement after a given height (nearly 37000m) and at a given latitude. I have his mass, area, parachute area, drop height, parachute deployment height, data about ...
1
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4answers
4k views
Free falling of object with no air resistance
Why does an object with smaller mass hits the ground at same time compared to object with greater mass? I understand the acceleration due to gravity of earth will be same but won't the object with ...
2
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2answers
193 views
How do I approach this conservation of energy problem, symbolically
In the absence of nonconservative forces such as friction and air resistance, the total mechanical energy in a closed system is conserved. This is why that when I toss an object directly upwards, the ...
10
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7answers
2k views
Would it help if you jump inside a free falling elevator?
Imagine you're trapped inside a free falling elevator. Would you decrease your impact impulse by jumping during the fall? When?
3
votes
4answers
654 views
Can a balloon float into space? (+orbital velocity)
After watching the recent "space jump" a question arose. Why can a balloon not float into space? Can one be made/designed to do this?
Next, everything in orbit is falling back to earth. It only ...
10
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5answers
7k views
jumping into water
Two questions:
Assuming you dive head first or fall straight with your legs first, what is the maximal height you can jump into water from and not get hurt?
In other words, an H meter fall into ...
2
votes
1answer
262 views
Radial fall in a Newtonian gravitational field [duplicate]
Suppose an object of mass $m$ starts at rest at a radial distance $ r_0$ from a perfectly spherical mass $M$ (where $m << M$), $r_0 > R =$ radius of $M$.
Can we analytically determine when ...
3
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1answer
333 views
Coriolis force in free fall
Does the coriolis force has any measurable effect in free fall from large heights?
Take for example the sky diving experiment by F. Baumgartner who started from a height of about 40 km above New ...
3
votes
3answers
417 views
Free falling objects
My teacher and I are in the middle of an argument because she says that if you were to drop two objects at the same time and the same height, but with different initial velocities, both of them would ...
8
votes
1answer
2k views
From how high could have Felix Baumgartner jumped without disintegrating like a shooting star?
Today Felix Baumgartner jumped from 39 kilometres high and reached the earth safely.
Just considering friction, from how high can a human jump?
I expect that from a certain height, he would have ...
0
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0answers
105 views
Free Falling of an object [closed]
A rock falls from a height X1 . Two seconds later , the second rock falls from a height X1-60 . From what height the first rock falls , and how much time did it take , if both of the rock fall at once ...
1
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3answers
239 views
when an object moves downward, is its height negative?
the question is:
A ball is thrown directly downward with an initial speed of 8.00m/s from a height of 30.0m. After what time interval does it strike the ground.
so i went through the problem and ...
0
votes
1answer
215 views
Energy used to stop / slow an object
I'm trying to workout how much energy (if any), I use (imagining me as an efficient machine rather than a complex bio-mechanical human) when I lower or catch a weight. I understand that when I push it ...
0
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2answers
2k views
Why do objects with different masses fall at the same rate? [duplicate]
Possible Duplicate:
Confused about the role of mass
Today we were in our Literature class talking about the Renaissance and the Enlightement and our teacher also said that scientific ...
1
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0answers
287 views
Newton's Law of Gravitation, Gauss Law and GR
From One of My Unpublished Papers
$$\frac{d^2 x^{\alpha}}{d\tau^2}=-\Gamma^{\alpha}_{\beta \gamma}\frac{dx^{\beta}}{d\tau}\frac{dx^{\gamma}}{d\tau} \tag{1}$$
For radial motion in Schwarzschild’s ...
0
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1answer
190 views
Time taken for object in space to fall to earth
The Problem
For a small mass a distance $R_i$ away from the center of the Earth, how long would it take for the object to fall to the surface of the Earth, assuming that the only force acting upon the ...
1
vote
1answer
146 views
How do I factor in multiple forces into these Newtonian mechanics equations?
Say a person is walking along.
He then jumps.
The person weighs $25$kg (irrelevant?).
Just after jumping, his velocity is 5m/s (positive is taken as up).
Gravity is taken as ...
0
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0answers
109 views
Confusing elevator Question , Please help by giving answer and detailed procedure [closed]
The given data is :
An elevator starts from rest and is uniformly accelerating at 2m/s2 . After 1 second , a person throws up a ball with initial velocity 4m/s. The hands of the thrower remain in ...
1
vote
1answer
696 views
Trajectory of projectile thrown downhill
I'm teaching myself mechanics, and set out to solve a problem determining the optimum angle to throw a projectile when standing on a hill, for maximum range. My answer seems almost plausible, except ...
3
votes
3answers
361 views
A freefalling body problem, only partial distance and time known
Well, I've been trying to figure out a problem which I imposed on myself, so no literal values included. Unfortunately, my brain is not cooperating.
The problem states:
What is the height from ...
4
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1answer
288 views
Did Galileo offer an explanation why his law of falling bodies is independent of mass?
Naively, (and endorsed by Aristotle) one expects heavier things to fall more quickly, Galileo Galilei showed in fact this is not correct, and that in fact how they fell as independent of mass (if air ...
-1
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1answer
1k views
Question on Projectile Motion equation [closed]
A golf ball is shot into the air from the ground. If the initial
horizontal velocity is 20m/s and the initial vertical velocity is
30m/s, what is the horizontal distance the ball will travel ...
2
votes
4answers
149 views
Why is the time taken for something to fall proprtional to acceleration due to gravity?
This is a continuation of this question.
I saw in a piece of writing (that I no longer seem to be able to aquire) on dimensional analysis that:
$$t \propto h^\frac{1}{2} g^\frac{-1}{2}.$$
How can ...
0
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1answer
222 views
Calculating the launch angle of a horizontal launch (mechanics) [closed]
I need some help with the following question:
A smooth spherical object (the first object) is projected horizontally from a point of vertical height H = 26.38 metres above horizontal ground with a ...
7
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2answers
271 views
Equivalence principle and radiation from falling particle
I am currently having a hard time solving a problem of GR from Lasenby's book.
I can't make it more clear than by quoting the exercise:
7.2 A charged object held stationary in a laboratory on the ...
2
votes
3answers
184 views
Why can't we think of free fall as upside down rocket?
/\
/ \
| |
| m |
| |
------ <--- floor (Rocket A)
This rocket is accelerated (g) upwards then mass(m) falls on the floor.
...
1
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4answers
239 views
Freefall in/out of an enclosed environment
I've just been learning about Einstein, relativity, and the equivalence principle in Physics. I'm fascinated with the idea of being inside a free-falling enclosed environment (such as, e.g., rocket, ...
0
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2answers
412 views
Basic Free Fall Problem [closed]
So I am trying to remember my childhood doing some Physics problems, but seems that I forgot almost everything. But it's not a big thing... that's why I'm training!
My problem is pretty basic ...
2
votes
6answers
591 views
Which person can handle falls from big heights better: lighter or heavier?
This probably includes a little of biology, but I believe it's mainly physics, so I hope it's ok to ask here:
Imagine 2 persons: Person A weights 120 pounds and person B weights 180 pounds.
Imagine ...
1
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3answers
782 views
Why is heavier object more reluctant to get falling down?
Is it because of the upward force that stops the object? for example-
2
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2answers
309 views
Is the speed of a person falling down different if doing a forward somersault during the fall?
Let's imagine this in an situation where a person jumps down from a smaller building, a garage for example. The exact numbers aren't really important here, since I'm not aiming for an exact answer, ...
8
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4answers
1k views
Water pressure in free fall
The increasing water pressure as you go deeper is generally explained in terms of the weight of the water column above the observation point pressing down. The question, then, is what would happen if ...
