Elevator Definition and 561 Threads

Hey! :) An elevator of an apartment building with $4$ floors begins from the ground floor with $5$ people.Calculate the number of ways of getting off the elevator of $0$ zero people at the first floor , $2$ at the second floor, $2$ at the third floor and $1$ at the last floor. I thought that...

What would be seen if a ball were projected at an angle to the horizontal in a falling elevator? Would the path be parabolic as always? And why?

Okay, so I know that if you are in a free falling elevator and you jump up you will hit the ceiling, something you could not do in an elevator that was still. But if the elevator was falling at a constant velocity, say 50 miles per hour, when you jump up will you also hit the ceiling because you...

Homework Statement "Consider a cable, of fixed mass per unit length, which extends radially from just above the surface to a distance ηR measured radially from the center of the Earth. By determining the total force on the cable, or otherwise, find an expression and numerical value for η. At...

A 60kg student is standing on a scale in an elevator that measures weight in Newtons. Calculate the reading on the scale if the elevator is accelerating down at 4 m/s^2...when the elevator is accelerating up at 4 m/s^2... and in free fall. Not sure if my work/answer is correct accelerating...

Homework Statement An elevator goes up 180 m by first accelerating at a constant rate of 1.0 m/s2, then staying at a constant speed of 9 m/s and then decelerating at a constant rate of -­‐‑1.0 m/s2. How much time does it take the elevator to go from bottom to top? so i know that d = 180m...

My apologies for asking two questions in a short period of time, this is the last question I have. Hopefully one day I'll be skilled enough to answer everyone elses! :) Homework Statement An empty elevator has a mass of 722 kg. It moves between floors at a maximum speed of 6.00 m/s. The...

Homework Statement You are standing on a spring balance in an elevator. Draw a graph of scale balance reading VS time. At T0 you are at rest, accelerate upwards until T1 (where you reach constant speed) then decelerate from time T2 to T3. Homework Equations N/A The Attempt at a Solution...

Homework Statement A cable lifts a 1200 kg elevator at a constant velocity for a distance of 35 m. What is the work done by (a) the tension in the cable and (b) the elevator's weight? Homework Equations W = fscos(theta) The Attempt at a Solution okay i already know the...

I want to make an elevator lift from an electric motor. The motor has a 42 mm shaft that turns at 1800 rpm. I want to lift approximately 200 pounds total twenty feet high, slowly and safely. I was hoping someone with knowledge of pulleys and gears could help me figure out what I need to...

Homework Statement I need to find the weight of a person who has mass 71 kg, and is riding an elevator, at different time intervals. The intervals are 1,5, and 9 seconds. I was given a velocity vs time graph, so I'll try to describe as best i can: The graph starts at (0,0), the slope is 4/1...

Henry gets into an elevator on the 50th floor of a building and it begins moving at t=0.00 s. His apparent weight is shown over the next 36.0s What is Henry's mass if his maximum apparent weight within the elevator is 900.0N? so shouldn't it just be: w = mg m = w/g = 900/9.8 =...

Homework Statement You are consulting for an elevator company. During a safety test, technicians created the following graph of the velocity of the elevator versus time; you have been asked to interpret the graph. Unfortunately, you are told that the technician who printed the graph has made...

Homework Statement A woman stands on a scale in a moving elevator. Her mass is 50kg and the combined mass of the elevator accelerates upward. During the acceleration , the hoisting cable applies a force of 9350N. What does the scale read during the acceleration ? Homework Equations F...

hello, if i am traveling upward in an elevator with acceleration a, would the net acceleration be a-g? thanks.

A block of mass m is suspended from the ceiling of a stationary elevator through a spring of spring constant k.Suddenly the cable breaks and the elevator starts falling.Show that the block executes S.H.M of amplitude mg/k in the elevator. I solved the problem applying a pseudo force mg on...

1. An elevator starts from rest with a constant upward acceleration and moves 1 m in the first 1.4 s. A passenger in the elevator is holding a 4.8 kg bundle at the end of a vertical cord. What is the tension in the cord as the elevator accelerates? The acceleration of gravity is 9.8 m/s^2...

Homework Statement Starting from rest, an elevator accelerates uniformly between the 1st and 2nd floors, and decelerates uniformly between the 5th and 6th floors, coming to a stop at the 6th floor. Between the 2nd and 5th floors, the elevator covers the 6 meter distance between each two...

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 = ma mg - Fn =...

An elevator cabin which weighs 3000 lb is lifted up 120 feet. It is connected with a counterweight of 3200 lb by a cable of length 200 feet weighing 4 lb per feet. What work is done (or gained) if a) the counterweight comes to rest at the same position as original position of the cabin, b)...

Homework Statement A simple pendulum is 5m long. What is the period of the oscillations for this pendulum in an elevator accelerating upwards at 5m/s2 and accelerating downards at 5m/s2Homework Equations ω = √(g/L) T = 2∏ / ωThe Attempt at a Solution I got the right answers (trial and...

Homework Statement A man is on an elevator - Draw a FBD of the man if the elevator accelerates upwards - Draw an FBD of the man if ele. accelerates downwards Homework Equations F=m*a w=mg The Attempt at a Solution My FBD For the first one "elevator accelelartes upwards" means...

I don't really know how to phrase this question. But what floor in a building takes the less time to wait for an elevator? Like for example. Say that there's a building with two elevators in it. Each floors are the same height. Each elevator travels at the same speed. The first floor has...

So If I remember right. The explanation as to why people in orbit appear to be weightless is cause they are in free fall. and because they are in an innertail frame we see them as weightless. this explanation bothers me some. cause I feel as though that innertail frame is still expieriencing...

So the school is trying to blame, and make us pay for the alleged breaking of an elevator on me and my two friends and we are trying to prove it is not possible. I need some physics help cause my last physics course was in high school. There were 3 of us, weighing 190lbs, 169lbs and 159lbs...

Hey guys i am very stuck any help appreciated. I do not know where to start. The equations used need to be derived from first principles and accurate free body diagrams drawn. An elevator moves downwards at a constant velocity v0. While descending, at a particular height (assuming t=0), the...

Homework Statement The numbers aren't important because I'm after getting a more intuitive sense of the problem. When an elevator is accelerating upwards with a mass in it on a scale. Why is the apparent weight the normal force? Homework Equations F=ma W=mg The Attempt at a...

A 1.6kg mass is suspended from a string in a stationary elevator. The spring stretches 12cm. The elevator now accelerates upward, and the spring extends a further 12cm. What is the acceleration in the elevator?

Very often the principles of faraday cage are extended to non electrostatic situations, i.e. situations involving time varying electric and magnetic fields. This means that the interiors of a metallic shell should be impervious to external time varying electric and magnetic fields. However, I...

From observation I believe that the moons of Mars may provide a landing and lift off platform . The moon Deimos is near to geosynchronous orbit and drops a tether to dangle over the orbit of Phobos above the surface of Mars . From Phobos a shoe swing is tethered out and dropped onto Mars as...

[FONT=Lucida Grande]5 people are on the 17th,19th,20th,26th and 31st floors.We have to get all of them out. [FONT=Lucida Grande]But the elevator doors open only when all of them are between the 21st and 25th. [FONT=Lucida Grande]There are 2 buttons,+8 and - 13,that will be activated only when 2...

Homework Statement Harold has a mass of 72.2 kg, and is standing on a scale in an elevator cab. What will the scale read if the elevator is moving downwards at a constant 0.050 m/s?Homework Equations The Attempt at a Solution Since the scale has a normal force upward and Harold has an...

Ok so this is silly and purely hypothetical... I am under the impression that should we ever decide to construct a space elevator we would need a pretty large mass on the space side of things. and that is one of the hurtles to making one. I am wondering if we have the capability to...

The cable of an elevator of mass M = 1640 kg snaps when the elevator is at rest at one of the floors of a skyscraper. At this point the elevator is a distance d = 36.4 m above a cushioning spring whose spring constant is k = 13600 N/m. A safety device clamps the elevator against the guide rails...

Homework Statement An elevator moves up with a constant acceleration a and a person stands inside the elevator. At time ##t_1## > 0, the person throws a ball directly upwards with velocity u wrt himself. Find the distance of the ball from the man's hand. (assume he does not move his hand)...

Homework Statement An elevator accelerates downward at 3.2 m/s2. What force does the floor of the elevator exert on a 46 kg passenger? Homework Equations T+F=ma T being tension The Attempt at a Solution I don't know if the tension of the elevator line is 9.81N, and in the...

Homework Statement Person weighing 0.9kN rides in an elevator that has downward acceleration of 1m/s^2. What is the magnitude of the force of the elevator floor on the person. Answer in units of kN. Homework Equations F=ma The Attempt at a Solution I drew a force body diagram...

Homework Statement A man pulls himself up, the acceleration is 1 m/s², the man's mass is 60 kg and the elevator's mass is 40 kg. a) Calculate the tension in the rope. b) Calculate the force that the man exerts on elevator's floor. Homework Equations Fr = Ma The Attempt at a...

An elevator weighs 3.0•10^3N. It accelerates up at 1.0m/s^2. What force does the cable exert to give it this acceleration? I know I have to find the mass first but for the acceleration, would it be gravity plus acceleration given : 9.80+1.0 ? f=ma Also for this question: A 20kg child steps...

Period for pendulum is T = 2π√(L/g) When a pendulum is in an elevator and it goes up T = 2π√(L/9.8+a) At rest: T = T0 Elevator moves upward with constant acceleration a = 3g T = 2π√(L/9.8+3g) So I have to solve for T0 T0 = 2π√(L/9.8+a) = 2π√(L/9.8+3g) T0 = (√(L/9.8+a))2...

I've read the forum rules where it says that graphical/violent content cannot be posted on the forum and I completely understand that. That being said, I will post this in hopes that someone out there can help me resolve an argument that my friends and I have been having ever since we came...

Question regarding the "elevator" acceleration resultant force Homework Statement In the "elevator" case, when a man is standing on a weighing scale, and the elevator accelerate upwards, the resultant force acting on the man will be UPWARD force, and the man is feeling "HEAVIER". So here is...

I'm not sure if I approached this problem correctly and would like some assistance. Homework Statement An elevator with a total mass of 800 kg is moving downward at 6 m/s. It slows to a stop with constant acceleration in 3 seconds. a) Find the tension T in the supporting cable while the...

Homework Statement An elevator weighing 10 000N is supported by a steel cable. Determine the tension in the cable when the elevator is accelerated upward at 3.0 m/s2 A) 7.0kN B) 10.0 kN C)11.6 kN D) 13.1 kN E) 40.0 kN Homework Equations F=ma W=mg (g=9.8m/s^2) The Attempt...

Homework Statement Hi everyone, I am just wondering how you would solve this question.. 2. Elevator Problem (Practice on Segmented Motion) A hotel elevator ascends 200 m with maximum speed of 5 m/s. Its acceleration and deceleration both have a magnitude of 1.0 m/s How long does...

Homework Statement A student stands on a bathroom scale in an elevator at rest on the 64th floor of a building. The scale reads 828 N. (a) As the elevator moves up, the scale reading increases to 919 N. Find the acceleration of the elevator. (b) As the elevator approaches the 74th floor, the...

Homework Statement Two blocks, each of mass m are hung from the ceiling of an elevator as in the figure below. The elevator has an upward acceleration a. The strings have negligible mass. http://imageshack.us/a/img856/2241/5p031.gif Find the tensions T1 and T2 in terms of m, a, and g...

Homework Statement .An elevator is moving at 1.1 m/s as it approaches its destination floor from below. When the elevator is a distance h from its destination, it accelerates with a = −0.55 m/s2. Find h Homework Equations vf^2=v0^2+2ax x=x0+v0t+1/2at^2 The Attempt at a Solution...

Homework Statement In the sketch at right, the winch W draws the cable at a constant rate of 2 m/s. Calculate the velocity of the counterweight C relative to the elevator E. Homework Equations (Sa-Sc)+(Sb-Sc)+Sb=I2 The Attempt at a Solution I must be using the wrong equation...

Homework Statement An elevator accelerates from the top floor at 100 m height downward with a uniform acceleration of a. After 5.0 s, an object is dropped out of an opening in the door, and that object hits the ground 3 s later. Find a. How high up was the elevator when the object was...