Fall Definition and 903 Threads

Homework Statement Two students are on a balcony a distance h above the S street. One student throws a ball vertically downward at a speed vi ; at the same time, the other student throws a ball vertically upward at the same speed. Answer the following symbolically in terms of vi, g, h, and t...

Homework Statement a stone is dropped from a cliff 200m high.if a second stone is thrown verticall upwards 1.50seconds after the first was released.strike the cliff base at the same instant as the first stone.with what velocity was the second stone thrown 2. Homework Equations Xf=xi +vt +...

Homework Statement A stone is dropped from rest from the roof of a 100-m high building; 2.00 s after that, a second stone is thrown straight down with initial speed v0, and the second stone passes the first stone 21.6 m above ground. (a) When are the stones at the same height? (b) What was the...

Homework Statement A stone is thrown vertically upward from the top of the tower with a velocity of 15m/s. Two seconds later a second stone is dropped from the top of the tower.if both the stone strike the ground simultaneously find the height of the towerV1i=15m/s V2i=0m/s t=2s h=? Homework...

Homework Statement An inquisitive physics student and mountain climber climbs a 50.0m high cliff that overhangs a calm pool of water. He throws two stones vertically downward, 1.00 s apart, and observes that they cause a single splash. The first stone has an initial speed of 2.00 m/s. (a) How...

I know that energy is recognized through motion. Even in the mass-energy equivalence a velocity is present even though it is a rest-energy (Not really sure if this would count as a potential energy since there is no 'field' of acceleration that the mass is in) So does kinetic and potential...

I already know that a hammer will drop to the ground on Earth the way it was held, but I don't understand why.

Two objects thrown from a cliff. One with + vinitial (upward) One with - vinitial (downward). Does the one with + vinitial not reach a greater height and thus have a larger vf upon hitting the ground since it falls farther and therefore is subject to gravity longer?

Lets say there is a rigid metal box. It is 1meter wide, 2meters long and an undetermined height. The thickness of the box's metal walls are also undetermined. The entire box weighs 2 metric tons. There is a person lying face down or face up in this box, and inside the box, the bottom and top of...

Homework Statement Write a C program to simulate a falling object. The program should ask for the initial height of the object, in feet. The output of the program should be the time for the object to fall to the ground, and the impact velocity, in ft/s and miles/hour. Your program should use...

So I have to calculate the initial velocity of an object I dropped from 2.195 meters that took .96 seconds to hit the ground, given that the Earth's gravitational pull is 9.81m/s^2. What direction/step should I first take in order to solve this? I'm not asking for the answer just a step or two...

I kind of understand how orbit works. So an object falls 10 feet then the Earth's curve counteracts the 10 feet, so it's prevents the object from just crashing down to earth. But wouldn't the object slowly either come closer to Earth or go away from earth. As in like millimeter by milimeter.

Homework Statement Using Newtons second law, if an object with mass M is free falling (the only F acting upon it is its own weight), calculate the object's acceleration. What would happen to its acceleration should its mass duplicate? Homework Equations F=ma The Attempt at a Solution So...

Homework Statement Calculate the length of time it would take for an object to fall 10.0m if g were one sixth the value of Earth's g. g=1/6(-9.8)= -1.633333333 m/s^2 a=-1.633333333m/s^2 displacement=10.0m[down] Homework Equations Maybe one of the big 5 kinematics equations? Or maybe...

how two objects hit the ground at same time regardless of their weight of masses. what is the reason of Acceleration is always constant via gravitational force for both of them. F=mg F1/m1=F2/m2

Homework Statement While parachuting, you dropped your sun glasses at a height of 1400m and it took 15 seconds for the glasses to fall onto the ground. What is your descend speed after you dropped your sun glasses? Homework Equations Y = VoT + 1/2at^2 The Attempt at a Solution My thought...

Homework Statement The Drop Zone drops riders 27m from rest before slowingthem to a stop. How fast are they moving before they start slowing down? vf=? vi=0, di=27m[up], df=om, displacement=27m[down], acceleration=9.8m/s^2[down] Air resistance is negligable Homework Equations...

Homework Statement I am analyzing free fall motion in my computer code class. We haven't really discussed much about air resistance and it is a bit of a foreign topic for me. I am searching the internet as much as I can for information on it, but would really appreciate talking to someone here...

Homework Statement I'm using ROOT (c++) to graph a numerical representation of the equation of motion. For simplicity, I am using initial velocity = 10 and initial height = 10. change in time = 0.05 so we find velocity by V_n = V_(n-1) -9.81*0.05 For some reason, this code is not giving me a...

Homework Statement I am tasked with coding some graphs regarding free fall motion. I am unclear what the professor means regarding the following, so I am looking for incite here. Problem: Solve numerically free fall velocity equation (problem 1.1), compare with exact solution (1.1) dv/dt =...

Homework Statement An elevator is ascending with a uniform velocity 2 m/s when a loose bolt gets detached from the ceiling and falls on the floor. If the ceiling is 3 m above the floor , find the time required by the bolt to fall from the ceiling to the floor? (g=10 m/s2) Homework EquationsThe...

I know it's really early in the year, but I want to have some opinion of my POTENTIAL fall 2016 schedule. No harsh comments.Taking calc 1 over the summer. I've been preparing since of December as I've been practicing my algebra skills. I'm taking Precalc this semester! There will be two...

My question is directed at anyone who currently is enrolled or was enrolled in Penn States PHD program as well as any faculty. Any other advise though would of course be appreciated. I was wondering what am I expected to be proficient in or to know prior to me starting in the fall semester...

Homework Statement Can free fall acceleration be determined by dropping a marble through a single photogate? The CPO timer attached to the photogate can measure the time it takes for the marble to pass between the arms. Knowing the diameter of the marble enables one to calculate the speed. If...

The facts are that the person is 183cm, 82kg, meaning his center of gravity is about at 105cm, he was running towards a railing of a balcony that is 108cm high, and allegedly hit the railing then fell over. Is this physically possible?

Homework Statement To escape the fire which has just declared itself in the building, James jumps through the window. One second before reaching the mattress, he traveled half of the height of fall. What is the total time of the fall in seconds ? What is the total height of the fall in meters...

I'm a second year grad student within engineering physics and after this I am going to take a master in theoretical physics. My plan is to go even further with a PhD when I am done. The thing is, I really don't enjoy some parts of my education. I love the theoretical part of almost everything...

Homework Statement Doing this from a memory of a final exam question from freshman physics that I could not solve 45+ years ago. A coin of radius R is poised at the top of another (fixed) coin of radius 2R. If it rolls with no slip, at what point will the top coin leave the lower coin. (I...

Homework Statement A 84.0-kg bungee jumper steps off a bridge with a light bungee cord tied to her and to the bridge. The unstretched length of the cord is 15.0 m. The jumper reaches reaches the bottom of her motion 38.0 m below the bridge before bouncing back. We wish to find the time interval...

Homework Statement A random sample of size n = 81 is taken from an infinite population with the mean μ = 128 and the standard deviation σ = 6.3. With what probability can we assert that the value we obtain for the sample mean X will fall between 126.6 and 129.4?The Attempt at a Solution z =...

Hi I'm trying to explain how this cartoon is physically impossible I know its impossible from common sense, but i don't know how to explain it using physics terms So my questions are: 1) Does the air resistance force have to be much greater than the Fgrav to make you land safetly? If so...

1. Homework Statement An electron in the H atom falls from n=(?) to n=3. The wave length of the emitted photon is 1100 nm. From what level did the photon fall? Homework Equations Used the following to get the Energy. w = c / v E = h * v E = h * (c/w) w = lambda (couldn’t figure out how to...

Suppose you have a weightless rod with at the endpoints two masses. This is a special rod whose length varies in time as a function L(t). If I consider this rod in free fall my intuition is that this rod will rotate for suitable L(t). However, I want to write down the equations of motions for...

Homework Statement Hi! I would need a little help with the following problem: We have found a new planet with density ρ and radius R, and drill a hole to its center. Then accidentally, one person falls into the hole. What is his velocity when reaching the bottom (the center of the planet)...

1. The problem statement, all variables andi given/known data A helicopter ascending at a velocity of 5.0m/s drops a bag at 105 m. How long does it take the bag to fall?Homework Equations X=vit+.5at^2 The Attempt at a Solution I've tried the equation above but i can't solve for time

Hi, folks. There's a somewhat popular hypothetical situation that involves a person falling into a hole dugg all the way through the Earth or any planet, passing straight to its center. Now, I understand quite well that the resulting motion would be periodical and the reasoning behind it. My...

I am confused about whether objects when a nonuniform mass density experience net torque during free fall. If you take a rod that is heavier on one end and lighter on the other, should it not experience a net torque and angularly accelerate? But at the same time, the acceleration by gravity is...

Homework Statement This is the second part of a two part question. The first part asked for the maximum force that can be applied to a bone with minimum cross-sectional area is 3.0cm2, Young's modulus 1.4 × 1010 N/m2, and can withstand a 1.0% change in length before fracturing. I calculated it...

Homework Statement A hockey puck slides off the edge of a table with an initial velocity of 20 m/s. The height of the table above the ground is 2 m. At what angle below the horizontal does the puck hit the ground? Homework Equations d=Vi(t)+(1/2)at^2 a^2+b^2=c^2 The Attempt at a Solution...

Why is gravity negative in certain equations, such as y = yi + vi t + (1/2) ( − g ) t^ 2 , but positive in others like vf^2 =vi^2 +2gh ?

Homework Statement A rope of uniform mass per unit length ##\lambda## and length ##L## lies curled on a table, with a short length ##\delta l## of it hanging through a hole in the table. At time zero, the rope begins to slide through the hole. At what time ##t_c## (in seconds) does the end of...

Homework Statement A rock is thrown straight down with an initial velocity of 10.5 m/s from the Verrazano Narrows Bridge in New York City. The roadway of this bridge is 70 m above water. Take upwards to be the positive direction. Calculate the displacement and velocity at a time of 1.0 s. The...

Taking: 1.Thermal Physics 2. Modern Physics 3. Advanced Lab now the big question 4. Computational Physics/PDEs/or independent studies (research)?

Summer vacation is quickly wrapping up :nb) Time to post your 2015 fall class schedule and share with us what you're taking. Also post when your first day back is :smile:

I'll be starting my junior year this coming fall, and I want to know what people think about my intended schedule. Quantum Mechanics I (3 cr.) Intermediate Electricity and Magnetism (3 cr.) Wave Motion and Optics Lab with Writing (4 cr.) Numerical Mathematical Analysis (3 cr.) Exploration...

The acceleration of free fall at the equator is not equal to the acceleration of free fall at the poles.explain?

remember saying my mate looked like a teacher and he didnt speak to me for the rest of the day.

Hello my name is Pablo, I'm new in the forum and couldn't find any similar post so i decided to ask. I have the following situation: In reference frame S (asumed stationary) there is a stick (length Lo in frame S) which falls from Yo at a vertical speed of 0.6c relative to S. In S the stick is...

Ideally I'd like to apply to graduate school for physics (leaning towards Astrophysics or Condensed matter); however, I don't think my course work or research is sufficient. I'm already using an extra year to complete the degree (I changed to physics the end of my Sophomore year) and wouldn't...

Hi there, the most basic formula from Newtonian gravitation is, for a free falling object, x = gt^2/2, where x is the displacement in the vectical direction, in the case of general relativity, this just happens to be for weak gravitational fields, for the sake of simplicity (trying to express my...