Free fall is any motion of a body where gravity is the only force acting upon it. In general relativity, where gravitation is reduced to a space-time curvature, a body in free fall has no force acting on it.
Questions tagged [free-fall]
550 questions
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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 in half—the halves clearly don't fall more slowly…
ErikE
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Why does a free-falling body experience no force despite accelerating?
Note: For the purposes of my question, when I refer to free fall assume it takes place in a vacuum.
From my (admittedly weak) understanding of the equivalence principle, falling in a gravitational field is physically indistinguishable from floating…
AdamJames
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Can a Skydiver Land On a Large Slide and Survive?
Please forgive my lack of artistic ability, but here's my question:
Consider that a skydiver, without using his parachute, were to fall exactly parallel to a giant curved slide that starts at $90\,^\circ$ perpendicular to the ground and gradually…
MegaMark
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Freefall into snow
In the movie Frozen, the following dialogue takes place:
Anna: "It's a hundred-foot drop."
Kristoff: "It's two hundred."
Anna: "Okay, what if we fall?"
Kristoff: "There's 20 feet of fresh powder down there. It will be like landing on a pillow...…
user3932000
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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 if the next step could be jumping from the…
Reactgular
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Which ball touches the ground first?
This is a very well known problem, but I can't find an answer in the specific case I'm looking for.
Let's consider two balls :
Ball 1 weighs 10 kg
Ball 2 weighs 1 kg
Balls have identical volumes (so Ball 1 is much more dense)
Balls have identical…
FlipFlapFlop
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5 answers
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 water is equivalent to how many meters…
Uri
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Is floating in space similar to falling under gravity?
In the case there is no air and your eye are closed,
then does falling from the sky under gravity have the same feeling as floating in space? Can our body feel that we are accelerating without the air hitting us.
If not how are they different?
Also…
34
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Cause of weightlessness
I'm a first year engineering student who is new to physics, so I apologize if my question is stupid. But in our statics course we are using the book "Engineering mechanics: statics" by R.C. Hibbeler and it contains the following image:
The…
SVolk
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32
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2 answers
Free fall ellipse or parabola?
Herbert Spencer somewhere says that the parabola of a ballistic object is actually a portion of an ellipse that is indistinguishable from a parabola--is that true? It would seem plausible since satellite orbits are ellipses and artillery…
user56930
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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 correctly, also I am wearing a ultra-oiled suit.
ajax333221
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Why do two bodies of different masses fall at the same rate (in the absence of air resistance)?
I'm far from being a physics expert and figured this would be a good place to ask a beginner question that has been confusing me for some time.
According to Galileo, two bodies of different masses, dropped from the same height, will touch the floor…
merwaaan
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26
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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?
user145
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Does a person inside a falling bus fall to the front of it?
So I was watching Final Destination 5 and something caught my attention. There's a part where a bridge collapses and everything falls apart, so there's this bus that has a person inside (unaware of what was happening) and it falls vertically (the…
R Los
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Does the weight of an hourglass change when sands are falling inside?
An hourglass H weighs h. When it's placed on a scale with all the sand rested in the lower portion, the scale reads weight x where x = h.
Now, if you turn the hourglass upside down to let the sand start to flow down, what does the scale read?
I…
Gary Chou
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