# Tagged Questions

The tag has no usage guidance.

23 views

### Free falling object with air resistance, what's the velocity as a function of time?

So, I'm looking into how velocity can be represented as a function of time when the air resistance is also function of velocity. The force of drag is $$F_d = C||\vec{v}||\vec{v}$$ where $C$ is an ...
171 views

### What physics concepts support the observation of the book and paper falling together?

you place a sheet of paper on a book, it falls with it rather than being separated & slowed by air resistance. What physics concepts support the observation of the book and paper falling together? ...
45 views

### How can I clarify the difference between free falling and Newton's law?

After I have viewed two experiments the first about Newton's law which involves a brick block and feather letting them fall one time in a vacuumed room they fall at the same time and another time in ...
42 views

### Find Time it Takes For an Object in Free Fall To Hit Ground With Given Gravity [closed]

Sorry if this seems like a simple question. I'm not that good with physics but I'm willing to learn! So my question is, how can I find the time it takes for an object at "h" height to hit the ground ...
115 views

### Does center of mass affect how an object falls?

Suppose you drop an object which has tow ends, of which one is heavy and the other is pretty light. Will the object fall with its heavier end downward or with the lighter one? Why does it happen?
58 views

### Introductory physics: first second of free fall

While doing my physics homework I encountered an acceleration problem that I've been unable to solve. Here, is the data table of the objects motion. At 1 second, why does the "Dist-meters" slot of the ...
73 views

### Will I die from a 50-foot fall? [closed]

Sorry if I didn't ask this in the right place, but... Will I die from a 50-foot fall? What are the chances of survival? I know this is more of a biology question or something, sorry :(
57 views

### Application of Mean Value Theorem to Law of Universal Gravitation

I'm not terribly well-versed in physics, so forgive me if this is trivial. Supposing an object hovers $6*10^5$ metres above Earth's surface, calculate its impact speed after falling to earth's ...
3k views

### Gravity - What happens when two objects of unequal masses fall freely towards the ground? (Revisited)

The common perception regarding what happens when two objects of equal sizes but unequal mass are allowed to fall freely towards the ground is that - both the objects make contact with the ground at ...
81 views

### Derivation of a kinematical equation [duplicate]

My question is, we can calculate distance of free falling objects with the equation of $d = \frac{1}{2}gt^2$ where $d$ is distance in meter, $t$ is time in seconds, but I wonder how we achieved this ...
84 views

### Free fall and gravitational time dilation

An observer A at rest in a gravitational field has some amount of time dilation relative to an observer B far away from the gravitational field. Would the clock of an observer C in free fall at the ...
149 views

### Do free falling observers see gravitational blueshift?

Observers at rest in gravitational fields will see infalling light signals as blueshifted. Do inertial observers in free fall in a gravitational field see the same shift? If someone is standing on a ...
7k views

### 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 ...
57 views

### Will a cyclist be able to pedal during free fall?

Assume that he is seated on the cycle and his waist is tied to the seat.
74 views

### Reach @ jumping from one building to another

Let's assume I'm in the rooftop of a building (Building A) and want to jump to the rooftop of another building (Building B). Forget about injuries... is just hypothetical. Building A has a height of ...
2k views

### Force of an impact on water

Today, at the Brazilian news, I heard that a men fell from a cruise into the sea, from a height of 50m, and decided to see if he could have survived. I took his weight for being 80kg. I did ...
48 views

### Are these two equations correct? [closed]

I know this is a pretty simple question, but like there should be room for those as well. I have the following two formulas describing how long it'll take for an object to decelerate. For example if ...
45 views

### Hammer will fall faster than the feather on the moon. 10 second thought experiment! [duplicate]

Please explain where my logic is wrong. a) Ignoring air, the same bowling ball will fall faster on Earth than on the Moon. b) Now, for the feather and hammer on the Moon, reverse your point of view ...
130 views

### Infalling light signals seen by a free falling observer

In this question/answer Does someone falling into a black hole see the end of the universe?, it is stated that an observer free falling toward/into a black hole will not see the end of the Universe ...
40 views

### Why will you float in free fall with 0 relative acceleration?

Imagine you are in an elevator that is falling freely to the surface of the earth. You begin to float. However you and the elevator have equal acceleration. Why is it that you begin to float with ...
I'm trying to cook up an equation that will give me position for a projectile which operates in the Newtonian Domain. So a the fall equation is: $$\mathbf{p_t} = \frac{\mathbf gt^2}{2} + ... 2answers 69 views ### How does general relativity explain the impact force after radial inward fall toward Earth? I understand that, in the context of the Schwarzschild spacetime (General Relativity), a radially inward falling observer follows a time-like geodesic with zero four-acceleration. There are no forces ... 0answers 48 views ### If I throw an object from the roof of a high building, how does it fall? [closed] Is it pulled towards the wall? And if so, what causes the pull? 1answer 35 views ### Calculate the distance of a falling object and terminal speed [closed] I have a homework problem that I would like to verify that I am doing it correctly. If anyone could help me see where I'm going wrong with the steps, I would really appreciate it. (a) Consider a ... 1answer 37 views ### Solve the inverse function of the solution to a varying acceleration problem ODE Suppose there are two positive charges A and B, both with equal mass m and the same charge quantity q. The initial distance between AB is R; and the initial velocity of B relatively to ... 1answer 45 views ### What's the average speed (along z) and the average position (along z) of an object in free fall? I'm looking to calculate the average speed (along z) and the average position (along z) of an object in free fall. The initial instant is t_0 and we have: z(t=t_0)=z_0 v_z(t=t_0)=v_0=0 I ... 0answers 37 views ### Galileo proved wrong? [duplicate] Galileo stated that objects dropped from the same height will hit the ground at the same time, that the rate of gravity is constant for all objects no matter the mass. But I think there is a flaw in ... 1answer 79 views ### Mimicking Free Fall I was thinking about this situation with a friend of mine, and we had opposing views: Suppose you have a frictionless table with mass M resting on top. You attach a chain to the mass M, a chain with ... 2answers 64 views ### 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 ... 1answer 208 views ### Two objects at different heights, would they be traveling the same speed? If I were to drop an object at a height of 15 feet, then another object of the same mass at 20 feet, would both objects be traveling at the same speed? What would be the speed of which they are ... 0answers 124 views ### Impact force on a Full Suspension Mountain Bike I have a full suspension MTB design and i will do a structural analysis using a FEA tool.For this purpose,i have to calculate the forces applied on both wheels when the bike falls from a certain ... 0answers 139 views ### 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 ... 1answer 49 views ### Physics Problem: Falling Rocket [closed] A rocket, of mass M = 40kg, falls vertically with a speed of 60 m/s = v_0 and explodes in two fragments of the same mass when it's at H=2km from the ground. Immediately after the explosion one ... 6answers 6k views ### 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 ... 3answers 269 views ### What acceleration to use in this problem? A balloon starts rising from the ground with an acceleration of 1.25 m/second square. After 8 second, a stone is released from the balloon. Find the time for stone to reach ground, distance ... 3answers 915 views ### How does artificial gravity reduction (weightlessness) work on Earth? Some of us have been to those amusement park/carnival/theme park rides where you enter some capsule/machine, and you will float, etc. There is also some other thing where you go inside a big room ... 3answers 655 views ### How do these factors affect the free fall of objects? Take an example of two balls of different masses being dropped from about 250 meters from the ground. How do the following factors affect free fall: Air resistance. Absence of air resistance. ... 2answers 71 views ### Will the gravitational pull of air affect the falling rate of an object? After looking at this question: Don't heavier objects actually fall faster because they exert their own gravity? A thought occurred to me that due to the increased gravitational pull of the ... 8answers 10k views ### 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 ... 1answer 108 views ### Probability Density of a freely falling body The following question has been taken from David J Griffith's Intro to QM. This is not my homework! :D Suppose I drop a rock off a cliff of height h. As it falls, I snap a million photographs, at ... 1answer 116 views ### Free-fall path into a black hole in Kruskal Coordinates If an object at t=0 begins to free-fall into a black hole from X in Kruskal coordinates (https://en.wikipedia.org/wiki/Kruskal%E2%80%93Szekeres_coordinates), what does its path on the Kruskal-Szekeres ... 4answers 507 views ### Why is displacement negative during free fall? I am confused by this question. Displacement is shortest path travelled by an object, but I had seen in my book that during free fall displacement is negative. 6answers 5k views ### 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 ... 5answers 5k 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 ... 3answers 122 views ### How can you explain objects of unequal masses falling at the same rate using GR? Isn't gravity caused by the curvature of space-time, and the stronger it's curved the stronger the attraction? it makes more sense to me that if a heavier object is falling on earth it would fall ... 2answers 106 views ### What is the highest possible space dive free fall? The world record is 136k feet but how high could it be without burning up. I know someone asked if u could jump from ISS which wouldn't be a free fall. Using any means of transportation. The record ... 8answers 34k 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 ... 3answers 2k views ### 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 ... 1answer 69 views ### How can I solve this differential eqution with IVP? [duplicate]$$m\frac{d^2r}{dt^2}=-G\frac{Mm}{r^2}, \qquad r(0)=R ,\qquad \dot{r}=v_0>0 describes the free fall of an object of mass $m$. $r(t)$ is the distance of m to the center of the earth which is $R$ ...
$F=ma$. Falling from any distance, mass stays the same, and acceleration due to gravity stays the same. So, why does it hurt more, the longer you fall?