An elevator system in a tall building consists of a 800 kg car and a 950 kg counterweight joined by a light ca?
-
an elevator system in a tall building consists of a 800 kg car and a 950 kg counterweight joined by a light cable of constant length that passes over a pulley of mass 280 kg. the pulley is a solid cylinder of radius .700 meters turning on a horizontal axle. The cable does not slip on the sheave. A number of n people, each of mass 80.0 kg are riding in the elevator car, moving upward at 3.00 m/s and approaching the floor where the car should stop. As an energy-conservation measure, a computer disconnects the elevator motor at just the right moment so that the sheave-car-counterweight system then coasts freely without friction and comes to rest at the floor desired. There it is caught by a simple latch rather than by a massive brake. (a) Determine the distance d the car coasts upward as a function of n. Evaluate the distance for (b) n = 2, (c) n = 12, (d) n = 0. (e) For what integer values of n does the expression in part a apply? (f) Explain your answer to part (e). (g) If an infinite number of people could fit on the elevator what is the value of d? If anyone could please help with part a (that's all I would need) it would be greatly appreciated. I have no idea where to start. Thanks in advance
-
Answer:
1. Calculate the total inertia of the system (it is a function of n). 2. Then calculate the total force pulling down the car (it is only positive for n=2,3,...) 3. Now you know the force and the mass, you can find the distance traveled using: energy = Fs = 1/2 mv^2 where F is the net gravitational force and v is the speed of the car at some point, and s is the distance traveled while the force is F. m is the inertia you calculated in part 1. For part 1, you need to get an expression for the pulley: not all of the pulley mass adds to the system. However, all of the counterweight and all of the car and the people contribute to the inertia. For part 2, just use F=mg with different masses. Hope this helps you get started on the problem. I guess the solid cylinder pulley is the hardest part. I'd compute the effective mass through integration, but perhaps they gave you some other formulas to work with?
Bas Joosten at Yahoo! Answers Visit the source
Other answers
1. Calculate the total inertia of the system (it is a function of n). 2. Then calculate the total force pulling down the car (it is only positive for n=2,3,...) 3. Now you know the force and the mass, you can find the distance traveled using: energy = Fs = 1/2 mv^2 where F is the net gravitational force and v is the speed of the car at some point, and s is the distance traveled while the force is F. m is the inertia you calculated in part 1. For part 1, you need to get an expression for the pulley: not all of the pulley mass adds to the system. However, all of the counterweight and all of the car and the people contribute to the inertia. For part 2, just use F=mg with different masses. Hope this helps you get started on the problem. I guess the solid cylinder pulley is the hardest part. I'd compute the effective mass through integration, but perhaps they gave you some other formulas to work with?
Bas Joosten
Related Q & A:
- Is there any way possible to hook up a Speaker Home Theater System in a car?Best solution by answers.yahoo.com
- Can you get a temporary permit for both a motorcycle and car at the same time?
- How to install a GPS System in a car?Best solution by eHow old
- How can I fix a light weight(1.5 kg) lighting fixture on the Cieling without screws/nails -Maybe stickypad/tape?Best solution by Yahoo! Answers
- Would a drop of sweat on a capacitive touchscreen be considered a touch?Best solution by Yahoo! Answers
Just Added Q & A:
- How many active mobile subscribers are there in China?Best solution by Quora
- How to find the right vacation?Best solution by bookit.com
- How To Make Your Own Primer?Best solution by thekrazycouponlady.com
- How do you get the domain & range?Best solution by ChaCha
- How do you open pop up blockers?Best solution by Yahoo! Answers
For every problem there is a solution! Proved by Solucija.
-
Got an issue and looking for advice?
-
Ask Solucija to search every corner of the Web for help.
-
Get workable solutions and helpful tips in a moment.
Just ask Solucija about an issue you face and immediately get a list of ready solutions, answers and tips from other Internet users. We always provide the most suitable and complete answer to your question at the top, along with a few good alternatives below.