Elevator Definition and 567 Threads

My friend has asked me for a formula that will solve his kid's elevator game. Imagine an apartment building with an infinite number of floors, both + and -. You start on an arbitrary floor, say 11. The game asks you to meet your mother on the 61st floor (the actual goal floor changes). But the...

Consider an "unidimensional elevator" of size L accelerating w.r.t. a given inertial reference frame. Suppose each elevator's point accelerates with a constant proper acceleration ##g## according Rindler acceleration profile. In the given inertial frame with coordinates ##(x,t)## the elevator...

It seems to me that the concept of a space elevator does not take Coriolis force into account. If the elevator were in built with a space station in geosynchronous orbit and counterweight then there is more to reaching the space station than just climbing the rope. The rope would have to be...

According to an inertial observer the electric field of a charged ball sitting on the floor of an accelerating elevator is contracted more than the elevator is contracted. So the inertial observer concludes that an observer inside the elevator will measure that the Coulomb-force from the ball is...

Homework Statement An elevator takes a 70 kg person from street level to the top of a 400 m sky-scraper in 4 minutes. The mass of the elevator is 500 kg. a] At what rate is the elevator plus the person gaining potential energy? b] What power is the elevator plus the person experiencing as...

Imagine that you are using an elevator and - due to some cause - all of the cables supporting it cracked and the brakes were not engaged - the elevator is in a free fall. Now, would it be technically possible to jump in that elevator? Jumping requires the force of reaction of the ground, this...

Homework Statement a) research the space elevator concept. Consider the environment in which the cable must operate. Recommend two physical and one chemical property that the cable should have. Justify your choices. b) Based on what you have learned about bonding and forces in solids, which...

Homework Statement A loaded elevator acge has a mass of 1500kg and a countermass of 1000kg. The cage is accelerated with 2m/s² to 1,4m/s and lifted to a height of 15m and stops at stand still. The inertia of the motor or the radius of the cablewheel is NOT given. The steady state speed of the...

[Moderator's note: This is a portion of a post originally made in another thread, which has been moved due to being off topic there.] Einstein's Equivalence principle is based on the realization that, "An observer in a windowless room cannot distinguish between being on the surface of the...

Consider a hypothetical scenario where you are present in an elevator which is either at rest or is moving with constant velocity (ignore cases of acceleration when elevator stops/starts moving). Now how will you determine if the elevator is moving or not given that there are no windows in the...

Homework Statement The following task causes me problems: The science fiction writer R.A. Heinlein describes in the novel "Friday" a satellite ("space elevator"), which consists of a long rope, placed directly above the equator. The rope is aligned along the Earth's radius. It moves so that...

A 5m tall elevator travels uniformly up an elevator shaft at 8m/s. At some point in time, a bolt falls from the top of the elevator and falls freely down the shaft. You can ignore the effect of air resistance. How many seconds after the fall will the bolt pass the bottom of the elevator? y=yi +...

Homework Statement An 82 kg man inside a 40-kg dumb-waiter pulls down on the rope. At that moment the scale on which he is standing reads 209 N. Determine the elevator's acceleration. Homework Equations F=ma The Attempt at a Solution I know the acceleration is 0.152 m/s^2 upwards , I need...

Homework Equations P = W*V Fnet = ma V = 3.0 m/s W = 29.9[/B]The Attempt at a Solution I think i got this wrong, but I want you to check if my answer is right :( Heres what i did: So, P = force * velocity P =force*3.0 m/s force = force due to gravity + acceleration (net force) is F = ma =...

Homework Statement Say I have two objects on top of each other in an elevator (say Object 1 on the bottom and Object 2 on top), each with a given mass. The elevator is accelerating downward (meaning the elevator is moving up and slowing down). What would the normal force be on Object 1...

Homework Statement A teacher rides in an elevator that moves upwards at a constant velocity and holds a set keys 1.00m above the floor of the elevator. After 2.00 seconds of moving upwards from the ground level of the science building, theteacher releases the keys from their hand. Relative to...

Homework Statement Three masses (m1=3.2, m2=9.6, and m3=6.4) hang from three identical springs in a elevator with a spring constant of 349N/m. The elevator is moving downwards at -3.7m/s and accelerating downwards at a= -2.5m/s^2. What is the magnitude of the net force on the middle mass...

Dear Everyone, A sphere is attached to the ceiling of an elevator by a string. A second sphere is attached to the first one by a second string. Both strings are of negligible mass. Here $m_1=m_2=m=3.52\text{ kg}$. (a) The elevator starts from rest and accelerates downward with...

Homework Statement A 100kg man stands on a scale in an elevator moving downward. If the elevator decelerates at ##2 m/s^2##, determine the scale reading (in kg). Homework Equations ##N = -WT = -Mg## The Attempt at a Solution ##-WT = -100(g)## ##-WT = -100(-10)## ##-WT = 1000## ##Ma =...

In an elevator "vertically" accelerated at g in outer space, the equivalence principle says a "horizontal" light ray in the elevator looks like a parabola. I completely understand that the light ray is curved but don't understand why the deflected light ray is an exactly parabola. Almost all...

Hi guys, I know this is a really simple question, but I'm just making sure I have this concept down: Scenario 1. An elevator accelerates down at 9.8m/s^2. Scenario 2. The elevator cable is cut. If someone is inside an elevator, scenarios 1 and 2 would feel exactly the same to them, correct...

Say you have an elevator that reaches space. I have 2 questions : 1) say a space rock hits the top of the elevator... that would create a torque = force * distance on the ground... Wouldn't it instantly snap from any light force or space junk hitting the top of the elevator? Would the station...

Homework Statement Homework EquationsThe Attempt at a Solution A) W.r.t. Earth's frame, After 2s , velocity of bolt = at = 1.2*2 = 2.4 m/s distance traveled = (1/2) 1.2*22 = 2.4 m Let's say that the bolt reaches the floor at time t. Using s = ut + (1/2)at2 2.4 = 2.4t +(1/2)(-9.8) t2...

Hey! :o I am looking at the following: In a high-rise building with ten floors above the ground floor an elevator is installed. Suppose that twelve people enter the elevator on the ground floor and independently select one of the ten floors under uniform distribution. In how many floors does...

This is a rather old issue, but one that has recently been on my mind. We often say that gravity is the curvature of space-time, with good reason. At the same time, we also talk about the "gravity" in Einstein's elevator, as an example of the equivalence principle. This is also with good...

Homework Statement Homework EquationsThe Attempt at a Solution [/B] Initially , let the tension in spring be T Since hanging mass is just touching the weighing scale , T = 5g When elevator starts to accelerate upwards with acceleration 'a' , then on applying a fictitious force '5a'...

Suppose that a fly flies into an elevator and hovers in mid-air. The doors close and the elevator goes up. In analogy with a similar example (link), I imagine that the fly will travel up, it won't fall to the elevator floor. And I guess this is because the 'air' in the elevator, which is what...

Homework Statement An elevator containing three passengers (with a mass of 72 kg, 84, and 35 kg, respectively) has a combined mass of 1030 kg. The cable attached to the elevator exerts an upward force of 1.20 x ##10^4## N but friction opposing the motion of the elevator is 1.40 x ##10^3## N...

Homework Statement A 74.0 kg person is standing inside an elevator. The elevator is moving from the 3rd floor to the 21st floor. As the elevator passes the 4th floor it is moving at 2.30 m/s and is increasing speed at a rate of 1.43 m/s2 . At this moment, what is the normal force that acts on...

Afternoon everyone, I just found this awesome site where I thought I could enlist the help of a lot smarter people than myself with my project. I want to build a garage elevator to raise and lower various articles from my storage loft. My loft has 9' floor with a 15' ceiling. I was going to...

Homework Statement 1. John is traveling with an elevator upwards with the speed of 3.0m/s. She drops her bag. How big will the acceleration be right before it hits the elevator floor? My answer is 9.82m/s^2 is that correct? 2. Assuming the bag is 1 meter above the floor with an weight of 1 kg...

Greetings, For my school's project, I have to design an elevating system. Its main function is to continuously elevate a fertilizer disorderly and in bulk (rate of flow ~ 300 tonnes per hour, height of the elevator /course ~ 20 meters, the fertilizer is at 70°C, 5% humidity). My request is as...

It occurs to me that any force which acts on all of your atoms individually (as gravity does) would have the same feature that one would not "feel" accelerated. We only detect acceleration because parts of the system are acted on by different amounts right? When we accelerate in a car, the seat...

Homework Statement [/B] For this problem, use g = 10 N/kg. As shown in the figure above, a pulley is mounted to the ceiling of an elevator. The elevator is initially traveling with a constant velocity of 1.40 m/s, directed up. The rope (which we assume to have no mass) passing over the...

Homework Statement In a "worst-case" design scenario, a 2000-kg elevator with broken cables is falling at 4.00 m/s when it first contacts a cushioning spring at the bottom of the shaft. The spring is supposed to stop the elevator, compressing 2.00 m as it does so. During the motion a safety...

Does a conductor from space to Earth mess with the separation of charges in the solar system?

I recently came across this article (from 2005) outlining a proposal for a lunar space elevator: http://www.niac.usra.edu/files/library/meetings/fellows/mar05/1032Pearson.pdf Their is nothing in the article which stands out to me as being unrealistic, although the cost estimate ($10B) might...

Homework Statement Hi everyone,I just want to know if my answers are correct. Homework EquationsThe Attempt at a Solution 1. For each situation, indicate whether the normal force exerted on you will be gater tha,less than or equal to your true weight. a) Elevator starts to move down from the...

Homework Statement I work as a supplemental instructor for an intro physics class. As I was preparing my worksheet for this week I came across this problem. A basketball player can jump to a height of 55cm. How far above the floor can he jump in an elevator that is descending at a constant...

Homework Statement A lifting system can be modeled as two blocks of mass m1 and m2 hanging from two pulleys, connected by ropes to a third block of mass M = 100 kg, lying on top of a horizontal surface. There is gravity g = 9.80 m/s2. a) Ignoring at first friction, find an expression for the...

Homework Statement At t = 0, an elevator departs from the ground with uniform speed. At time ##T_1## a child drops a marble through the floor.The marble falls with uniform acceleration g = 9.8 m/s^2, and hits the ground at time ##t = T_2##. Find the height of the elevator time ##T_1##...

Homework Statement An elevator with a mass of 500kg goes up 30 stories in 12 seconds doing 12000J of work. Find how high the elevator goes. Homework Equations I'm not exactly sure what equations are needed for this question but in class we have been using these equations. Ek=1/2mv^2 Ep=mgh...

Dear PF Forum, I have a question regarding Einstein Elevator, which I believe there are many topics about this. But I haven't got the answer. I've watched some youtube video or read about it, I forgot. That our head is wiser than our foot, because time slow for our foot. Okay..., this could have...

In the above case, the normal force exerted by the elevator on the box would be = 10kg * g + 10kg*5m/s^2, assuming g = 10m/s^2, the elevator would exert a normal force of 150N on the box. But wouldn't the box exert an equal and opposite force on the elevator resulting in no motion? I know this...

Homework Statement A 60.0 kg student is riding the elevator at the CN Tower in Toronto. Calculate her apparent weight if she is accelerating upwards at a rate of 5.20 m/s2. Calculate her apparent weight if she is riding down the elevator. Include a solution with the derived equation for each...

Homework Statement You are standing on a scale in the elevator. You weigh 500N. What would happen to the scale reading if you slow down, going upwards? Homework Equations - The Attempt at a Solution My answer: Acceleration would occur in the downwards direction because if you decelerate in...

Homework Statement A 65-kg woman descends in an elevator that briefly acclerates at 0.20g downward when leaving a floor. She stands on a scale that reads in kg. (a) During this acceleration, what is her weight and what does the scale read? Homework Equations ƩF = maThe Attempt at a Solution I...

Homework Statement Homework Equations So I've been thinking about this one for a while and I've tried to read up about Power in general. I think Power = Work/ Time = (Force x Distance)/Time or Force x Speed. The Attempt at a Solution F = ma, so if velocity is constant, a = 0. So that would...

Homework Statement An elevator moving downward at 4.00m/s experiences an upward acceleration of 2.00m/s^2 for 1.80seconds. What is its velocity at the end of the acceleration and how far has it travelled? downward acceleration=-9.8m/s^2, upward acceleration=2.00m/s^2. time=1.80seconds. Initial...

Homework Statement Energy conversion efficiency of the elevator is 80%, it is working from 220 volts. How much current does the electro motor consume while it is constantly lifting the 500 kg cabin at 2 m/s. The attempt at a solution I=P/U, so I figured I need to know the power. P=F*v. I...