# Tagged 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 ...
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### 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 ...
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### 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 ...
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### Curved paths through spacetime when standing still?

I have heard that falling objects fall at the same rate irrespective of their mass. They are 'following straight line paths through curved spacetime'. Does this mean that objects that accelerate in ...
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### 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 ...
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### Acceleration of an object dropped inside an accelerating elevator

A stone is released from an elevator going up with acceleration of $g/2$. What is the acceleration of the stone just after the release? The answer is $g$. Shouldn't the stone carry the acceleration ...
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### I know that free fall in vacuum is independent of mass. But what happens in air?

Pardon me if this sound somewhat trivial to some of the highly qualified users here. So I know two objects will fall at the same rate if they are in absolute vacuum, so what I'm assuming is that the ...
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### Is Galilei's reasoning on free fall valid?

Galileo Galilei discovered by experiments that all bodies tend to fall with the same rapidity (I use it in an intuitive sense, you can replace it by 'acceleration' used in today's physics language), ...
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### Is the Moon freely falling towards the Earth?

The Moon is revolving around the Earth and its centripetal acceleration is towards the Earth. Does it mean that the Moon is freely falling towards Earth? What is the cause of the Moon orbiting around ...
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### At what speed would you die upon impact with water?

If we hit the water at great speeds, we die. This is because the water has no time to "move out of the way" and acts as a "solid" surface. At what falling speed can we consider the water as a 'solid'...
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### Schwarzschild metric, speed of ball as measured by observer who catches the ball, just before ball is caught? [closed]

Inspired by this question here. The Schwarzschild metric, describing the exterior gravitational field of a planet of mass $M$ and radius $R$, is given byds^2 = -(1 - 2M/r)\,dt^2 + (1 - 2M/r)^{-1}\,...
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### 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 ...
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### 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 ...
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### Were there any efforts made by early physicists to discover and explain how composite bodies fall?

At the dawn of the modern era, Galileo discovered and described how composite bodies fall through the air (or at least the discovery is usually attributed to him). I'm interested in whether this had ...
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### 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, ...
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### 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 ...
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### 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 $x= \frac{1}{2} at^2$, $t=\sqrt{2x/a}$ $v=at$, ...
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### 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 ...
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### Terminal speed of a body in a gravitational free fall? [closed]

What speed would a small body moving towards a large body reach under gravity alone? More importantly, is there a 'terminal speed' for the small body due to the increasing energy required to ...
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### 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 ...
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### Free-Fall Lab Help - Getting weird results

So, I am doing a free-fall lab for my physics class. We got the values and I have the results here(we used a infrared photo-gate). Basically, we have a brass cylinder and a wood cylinder. Each are ...
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### Free falling of object with no air resistance [duplicate]

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 ...
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### Gravity and bottomless pits [duplicate]

Assuming that someone is theoretically able to make a hole through the center of a large planet, and then jumps down the hole, what will happen? Given my understanding of gravity and energy, my ...
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### Are time and gravity affected when at rest compared to free fall?

A falling object moves along a geodesic path ('straight path') in spacetime. When it comes to rest it now follows a 'curved path' through spacetime. Is the passage of time and force of gravity ...
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### Dropping Objects of Different Masses

It's a commonly taught principle that dropping two objects of different mass at the same height, given that there is no air resistance, will result in the two objects making contact with the ground at ...
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### What happens to gravity in the middle of the earth? [duplicate]

So I was curious about, what if we make a tunnel from one side of the earth, to the other side of the earth? Gravity is ofcourse always negative, which makes you "fall" and not "float". If we take ...
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### 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 ...
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### 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 ...
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### Why is it easier to drop on to a downslope?

On a bicycle, why is it easier to land from a drop or jump on a slope going downwards than landing on a flat surface or on an upslope? I've already heard answers such as "because that's how a bike ...
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### Why does a flat clover-like shape fall slower when it is rotating?

The plastic flat clover-like shape pictured below falls noticeably slower when it is rotating fast. I wonder why. Its three edges are flat, so I don't think that the rotation makes it act like a ...