Questions tagged [free-fall]
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.
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Is it easier to hit a ceiling of an elevator with a jump if the elevator is in the free fall?
In contrast to a popular question, here I want to hit a ceiling of an elevator. If the elevator is standing still, my legs are not strong enough to generate a jump that will help me hitting the ...
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Accounting for air resistance in a free fall experiment
Suppose we are working with masses of equal density. The effect of air resistance is bigger on objects which have a larger surface area $A$ (perpendicular to $g$). In a free fall experiment, this ...
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So I've found out heavier objects technically do fall faster? [duplicate]
Given the Earth's mass to be $M_E$, I know that $F_G = -\frac{GM_Em}{d^2}$, so the gravitation acceleration of a mass towards Earth is $g = -\frac{GM_E}{d^2}$. But what about the force exerted by the ...
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Why free fall motion is parabolic?
Consider no air resistance. If we throw a ball vertically upward from my point of view it goes vertically up and down and moving along straight line. But from point of view observer in outer space it ...
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Ground force on free falling object [closed]
Let a body be falling freely from height $h$ to the ground. Can we express the reactionary force $F$ acting on the body from the ground as a function of $h$, i.e. $F=F(h)$? (My attempt contains also ...
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Defining Free Fall: Does Gravity Need to be the Sole Force Present?
Can a scenario be considered free fall in physics if the work done by forces other than gravity is zero, but those forces are still present? Or is it necessary for gravity to be the only force present ...
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What does it mean that a falling mass in space doesn't sense any force?
I heard someone explain that if you were falling in space (i.e, a rooftop) you wouldn't sense gravity as a force acting upon you. But it would accelerate (≈ 9.8 m/s^2)
, which to me suggest that a ...
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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 ...
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Is the sensation of falling purely due to air resistance?
When I jump off of something, even with eyes closed I can be pretty certain that I'm falling due to the associated sensation of falling. However, as gravity should be affecting each of my internal ...
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How does unbalanced force ever create? [duplicate]
This question rather seems elementary but has been bugging me for a while! How does even unbalanced forces create? The main driving force of this question is Newton's third law
Let's take Free Fall:
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Ways of losing energy of a bouncing objects in vacuum other than Heat and Sound
When we released a bouncing object in a vacuum chamber, the object will fall, contact the ground of the chamber and bounce back up. We know that the object will not return to its original height ...
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Why won't a pen work on the International Space Station?
Today, in my physics class, we were discussing the effect of microgravity (specifically on the ISS) on various objects of everyday value. I learnt that a normal pen wouldn't work in space (So they ...
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Derivation of Proper Time of Fall in Schwarzschild Metric
Some time ago, in this question (Proper Time of Fall in Schwarschild Metric), I asked how to find the proper time of fall of an observer in the Schwarzschild metric because I had found many different ...
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Distance from Earth as a function of time [duplicate]
I'm trying to work on a problem involving modelling the distance of an object from Earth as a function of time (acknowledging that gravity changes with distance). This involves solving the ...
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Does weightlessness make no difference to free fall?
I looked up a lot of articles and questions about free fall motion and weightlessness. And I know there are a lot of similar questions.
In conclusion, I understand that there is no way to distinguish ...
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How does instantaneous velocity cause displacement in just one point? [closed]
I have a question.
Falling object graph is curve shape right?
And instantaneous velocity is tangent line but how does this velocity make displacement in distance? Because suppose instantaneous ...
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What is weightlessness? [duplicate]
I am having trouble understanding weightlessness in free fall. Why does person feel no force acting on him or her? For example, I feel when car is accelerating horizontally at 1g. Is it just the seat ...
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If a ball experiences a force when it hits the ground, why can we still use the kinematic equations to solve for its freefall time?
Suppose a question states:
A ball is dropped from a height of 2m. Find the time it takes for which the ball is in free fall.
To solve this, we would plug in our known values into the kinematic ...
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Frame of reference of a freely falling observer in General Relativity
Suppose I have an Einstein manifold (a manifold with a metric that solves the Einstein field equations. We can take $\Lambda = 0$ for simplicity in this example). The worldline of a freely falling ...
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Can a gravity-compensated accelerometer still measure or detect free-fall?
Take the simplest example of a plane aligned perfectly to the NED inertial reference frame at all time. The plane is restricted to only thrust or elevate upward or down with zero pitch, yaw, and roll (...
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Equation for position and velocity of a body falling in a gravitational field [duplicate]
I have tried asking this question on many forums and have so far failed to get a clear answer. Here is the problem. A body with a negligible mass is falling from a distance $R_1$ in a gravitational ...
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Why is it proclaimed for astronauts to be "falling"?
My physics teacher explained that the reason why it looks like astronauts are floating is because they are "falling". However, the way I think of it is that the outwards inertial force of ...
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If you drop a coin inside a car that is slowing down, where will the coin fall?
If you drop a coin inside a car that is deccelerating, where will the coin fall with respect to the vertical where you dropped it?
My thoughts where since it still has a velocity forwards, even ...
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Why an object with uneven distributed mass revolves when dropped from a height? [duplicate]
I was dropping a lego figure with its hands up and observed that it rotated when falling, it tried to drop in a position where its head was closer to the ground.
About this I did think that it might ...
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Body free fall calculation of the time durance as a direct derivation by time (non-relativistic)
Let's assume a body in free fall during 16 meters without resistance and I'd like to directly calculate the time of this fall.
Sure, one could painfully calculate:
$v^2 = 16 m·9.81 \frac{m}{s^2}$
$v = ...
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What is the weight of a body during free fall?
Is it '0' or is it equal to the product of the mass of the body and acceleration due to gravity? Please explain in relation to weightlessness of body in freefall.
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Could you feel your weight falling through the a tube drilled through the center of the earth?
Suppose you drill a hole through the center of the earth (assume the earth is uniform and no air resistance) and you jump in. Would you be "weightless" throughout the entire fall?
The reason ...
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How are objects kept free falling in the LISA experiment?
I'm watching a video about the LISA experiment, which will be used to detect gravitational waves.
In there, three space stations will be launched and will follow the Earth in its revolution around the ...
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Are all objects freefalling at the same rate inside a black hole?
We know the phrase "all objects move at the same rate when freefalling regardless of their mass" (interestingly this isn't even true because the objects are exerting their own gravity, but ...
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"Outrunning pressure": Liquid in free-fall
I've checked out related questions and didn't see an answer to my question.
Scenario: Liquid in open-top container, together accelerating downward with magnitude $g$. It was straightforward for me to ...
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If I dropped a golf ball straight down from about 5 meters, would air resistance cause a noticable change in the acceleration of the ball?
I am working on a Grade 11 physics lab report. I dropped a golf ball from a balcony 5m and 13cm off the ground. When I did all the calculations, the acceleration was 7,72m/s (calculations below). I am ...
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Speed of falling objects / with different altitudes
I have a question about gravity
So as we know gravity is significantly less on high mountains or tall buildings and increases as we lose height
☕ My question is that if we have 2 objects with the same ...
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Significance of time being dependent in many equations for gravity?
I have noticed, when browsing the equations for a falling body, it is often the case that distance is the independent variable rather than time. Take for instance, the time $t$ taken for an object to ...
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Non-parallel magnetic dipole falling throug copper tube
What happens with magnetic dipole while falling through copper cylinder?
If it's parallel to z-axis (shown on picture below with red color) we know that it stays parallel to the z-axis all the way ...
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Force components on dipole falling through copper ring
We have a magentic dipole parallel with z-axis (shown on the diagram below) falling through copper loop, because of changing magnetic flux there is induced current in cooper ring/loop and consequently ...
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Magnet falling in copper tube, radial force component
Consider a Dipole magnet falling through infinite copper pipe. If we displace a magnet a little bit so that the dipole isn't pointing to the same way as pipe (dipole isn't parallel to the pipe) we get ...
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Times of free-fall in different inertial reference frames in classical physics
Imagine that a ball is thrown directly down at a rate of 20 m/s from a height of 100m in Earth's gravitational field. If we were to calculate the time it takes to fall we could use the kinematic ...
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Why the Earth's gravitational acceleration is the same for every body? [duplicate]
As i understand forces gives bodys acceleration. And mass resist this acceleration. So why does every body, regardless of their mass, gains the same acceleration when they are in earths gravitational ...
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Proper Time of Fall in Schwarschild Metric
I've been trying to understand how the proper time of a radial fall into a black hole is finite, but I'm confused because I found many results and they do not seem to be the same.
Usually what I see ...
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Inertial to Gravitational Mass Ratio
According to Galileo's discovery the objects fall at the same rate due to the equality of inertial and gravitational masses. Where in our universe these two would not be equal? Following the question,...
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The value of $g$ in free fall motion on earth [closed]
When we release a heavy body from a height to earth. We get the value of $g=9.8 \ ms^{-2}$. Now, I'm confused about what it means. For example, does it mean that the body's speed increases to $9.8$ ...
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Free falling bodies in the absence of external forces
We know that if two balls $B_{1}$ and $B_{2}$ having masses $m_{1}$ and $m_{2}$ respectively and suppose $m_{1}$ is sufficient greater than $m_{2}$. In daily life observation, we see that both the ...
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Behavior of a loose coin on a free fall ride
At Six Flags over Texas, there used to be a free-fall drop ride called "the cliffhanger". Simply put, you got into a metal box, got elevated up to about 75 feet or so, and got dropped ...
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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 ...
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Shock testing equations (oversimplified?)
I'm designing a shock test tower with a maximum drop height of 1.8m. I'm adding bungee cords to add impulse and reach the intended 150G as it hits the programmer at the bottom.
My question is, is it ...
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Falling stones attached by a string
Suppose we have two stones, one "big" (A) and one "small" (B), the smaller one over the big one at the moment of free fall. Suppose also that a string of a certain length is ...
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Free Fall and constant acceleration
Although the acceleration of free fall is constant, why don't the distance go like $y = 9.8+4.9= 14.7m$ after 2 seconds, $y= 19.6+14.7 = 34.3m$ after 3 seconds? I think Constant acceleration work like ...
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Motion of free fall [duplicate]
We know that according to law of free falls object, all bodies fall with the same constant acceleration. But in distance formula ($s = \frac12 gt^2$), why the acceleration is just half?
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Is the acceleration of a falling object constant? Explain [duplicate]
My name is kakari john
I come from wiawso
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What would happen if when falling down you get pushed up?
I know it will be a weird question, but im not a physics well informed person and I had this unsolved question for long time.
What would happen if lets say you are falling with someone else from ...
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