Drive Definition and 528 Threads

I am hoping to build a shaker screen box, to sort sand from gravel and rocks. Want to use an eccentric drive gear to move the screen creating a vibration that would shift sand through screen mesh and over size rock wold flow off top of screen. Have not been able to find a source of eccentric...

Hello Everyone, I need your assistance here with the owing problem and I'm sure someoen will help me. :) I've trucking rates which are based on fixed kilos - the range starts from 50 kilos to 5000 kilos. Condition is whatever the volume of the cargo is we have to multiply it with 200 and...

https://www.physicsforums.com/attachments/250022 For the part (a), set the tension of the string that pulls the elevator be ##T_1## and the tension that pushes the counterweight be ##T_2##. Then we have the following equations: $$T_1−1200g=1200 \cdot 1.5$$ $$1000g−T_2=1000 \cdot (−1.5)$$ where...

I would like to read about the Alcubierre warp drive. Is there a good introductory paper? I have done some GR, round about 8 months worth in undergrad [mumble] years ago. And my honors project was on interior solutions for stellar collapse. So I'm OK with GR at about the speed of Weinberg's...

When the C drive gets limited in space, I take some space from the D drive and the audio files in D drive corrupted and can not open. How do I open these files?

This Quora post seems to say that this type of warp drive could allow faster-than-light travel, but somehow I think this is junk science: https://www.quora.com/Will-humans-eventually-be-able-to-explore-the-galaxy-After-all-it-is-multiple-light-years-away-to-even-the-nearest-star (author is...

I think it will be between 11 and 12 degrees but don't know how to re-arrange the equation or if I was even using the correct method

Hi, I've attempted to solve the first part (see file Position 1) in mathcad, but have no idea if it's correct, at least for the first part, as I am assuming, that the steps will be the same for the rollers in the remaining positions. So if I can manage to calculate the first one correctly, I...

I'm brainstorming how to make an electric motorbike, making as much use of the available space as possible to allow for as many batteries to be fitted as possible. Batteries aren't relevant right now; my focus is on the final drive at the back of the bike. To maximise space, I want to fit the...

Hello, I wanted to get a physics analysis of the best way to drive an electric car for maximum range. For example, would it be more efficient to drive on side streets at a slower speed of say 30 mph, or would it be better to get on the freeway and drive 60. Should I be accelerating as slowly as...

Hi All, I'm working on some design and apparently my physics expertise are getting rusty,i'd appreciate some help with the following:- I need to calculate the required torque for a stepper motor to rotate a solid cylinder with the following properties:- radius : 20cm height: 12cm density : the...

The graph is relationship between longitudinal force and slip ratio under the conditions of 0 longitudinal acceleration and flat road(0 angle of inclination). Which line represent FWD or RWD? Does FWD or RWD have higher maximum slip ratio?

Hello Friends, I have been wondering, is it possible to construct a motor, and attach a coil to it, such that with the motion due to the rotation of the motor, it generates a excess of energy that can be used to power the motor in turn, basically, could i use the excess to charge a battery that...

[Moderator note: This thread was moved from a HW forum. Hence the template. But it doesn't sound like homework.] 1. Homework Statement What will happen if i disconnect driveshaft from transmission and rev engine in drive? Homework Equations Rear end speed sensor could be play some role in...

Russia has developed a micronized nuclear powered drive for ballistic misiles and cruize misiles. This is obviously a very aggressive and environment polluting action. However, could such nuclear powered drive be used for space ships, that would start in space and do not touch the atmosphere of...

Homework Statement A man drives a car starting 5.00 km due West from the line marking the Eastern time zone. He travels at 30 m/s along a straight road that runs in a direction E 30° N. How much time does it take the man to get to the Eastern time zone? (The man must travel along the road: no...

I saw a conference from a Ligo physicist she said they are detecting gravitation wave of collapsing star. I also read the Doppler effect is working on gravity due to limited speed (c). I want to know if it is possible to detect a big mass traveling close to the speed of light in ours frame of...

Hi there! I am currently making a design about drive systems used for micro-hydro scheme. I don't know what type of driving element is suitable to used for transmitting the power from a turbine (cross flow turbine) to a generator. I'm planning to use both chain and sprocket & V-Belt Pulley which...

https://www.ncbi.nlm.nih.gov/m/pubmed/22552705/ Replicating past findings, no significant correlations between T and desire in men were apparent, but these analyses showed that the null association remained even when psychological and confound variables were controlled. Men showed higher desire...

I have acquired an old 1.5kW/2HP VFD [1] with aim to power a drill (which I don't have yet) with a three-phase motor from the single-phase outlet in my garage. It was supposed to be in working order, but alas it was not as the LCD display, for one, is only displaying gibberish (yes, I have...

Wondering if anyone knows anything about this. It was mentioned to me in passing. That on QNX, with an ETFS file system when you append to a file, that it completely rewrites that entire file to another location on the Drive. This presenting an issue with extra NAND flash writes ultimately...

I'm trying to understand calculation made Robert Zubrin in his presentation on Dipole Drive source: In here he made the following statement "A Coulomb of protons has a mass of 0.011 milligrams. If the jet power is 400 W, and the potential difference is 64 V, so the proton current will be...

It seems to me that if one had a functional Alcubierre drive and used it there would be some subluminal frame of reference in which time was going backwards for the spaceship which probably for it and for macroscopic objects in it which constitute a reasonably closed system would be a violation...

Hi I'm trying to connect two fly wheels together which are elevated on a bar and about 12 feet apart, the one wheel is driven by a motor and I would like the second wheel to be synchronised in rotation with it. Belts and/or chains are the obvious way forward but would it be difficult to connect...

I was reading this article about a possible warp drive that seems like science fantasy to me. https://www.universetoday.com/89074/what-is-the-alcubierre-warp-drive/

a belt is driven by a pulley at 33m/s the pulley rotates at 750 r/min. calculate: (a) the rotational frequency in r/s (b) the diameter of the drive pulley

Since it seems unlikely (to me) that current approaches will very rapidly stop the increase in CO2 levels driving climate change, alternative approaches involving removing CO2 from the atmosphere are being explored. Here is a link to a Science mag news article about using plantations to do...

If I need 50,000 Nm of torque to rotate a wheel, and I am rotating it about its rim (like the London eye), would 5 10,000 Nm motors each connected to a set of tyres to rotate it (the motors are not connected to each other), or would these motors first need to be connected to each other and then...

I was watching an excellent presentation of the theory of the Alcubierre warp given by Miguel Alcubierre himself at the 2017 Starship Congress (link below). At the 43:55 mark Alcubierre explains that the negative energy is located around the circumference of the craft in a toroid. I always...

Today for the first time in my Google Drive there appear several files in "quick access" labeled "you downloaded this month" although I did not explicitly download them, but were perhaps downloaded as part of a java script running somewhere on my computer, or maybe they are malware, that is the...

Hi folks, I'm currently working on the design of a triplex plunger pump. I have conducted an investigation into the loading of the pump at maximum operating pressure using an analytical method (free body diagrams) and using rigid body dynamics to validate. In both analyses the pump has been...

Hello, I've been wondering about this... If something like the Alcubierre drive is possible, that bends spacetime around it in order to reach great distances faster, why would this not affect other matter in its vicinity? If I'm understanding correctly, in order to move faster than light, a big...

Question One What would be the effect on the following if the load torque is increased and the speed maintains constant (give reasons for your answer): A. the tension in the tight side of the belt B. the tension in the slack side of the belt C. the power transmitted. Not sure on how to solve...

We know that belt drives are limited in their max possible power rating and most high power/torque applications(trucks) use gear drives. I wanted to know the main factor that limits the power/torque rating of belts. Is it Frictional slip or Belt material? If the frictional slip could be...

Hi, I'm and uneducated garage tinkerer currently motorizing a motorcycle dolly in order to rotate a motorcycle 180 degrees within its length to enable me to ride off and upon returning to my garage, to rotate the bike in order to drive out on my next ride. My question is what amount of ft-lb or...

I have no idea where this belongs or if it will be deleted but would Alcubierre drive cause detectable gravitational waves? And since I'm heading out on this limb would the direction of propulsion be indiscernible? As per the Wikipedia description it follows from a solution to the same general...

In driven SHM, we ignore an entire section of the solution to the differential equation claiming that it disappears once the system reaches a steady state. Can someone elaborate on this?

Homework Statement Belt coefficient of friction is .35, pulley diameter is 100cm and maximum torque is 200nm. Calculate the force on the tight side Homework Equations T2=T1/e^friction*angle The Attempt at a Solution T=fr, 200nm=f x .5m , f=400N T2=T1/e^friction*angle 400N=T1/e^.35*pie...

I am in a discussion with someone about the Alcubierre drive. I have doubts about it and he seems to think that Harold White experiments shows it can be built I am trying yo get an idea what current thought is on the drive. I know the drive does not violate general relativity but what about...

Hi all, Hope this is not too simple/dumb: When we save , say a Hard drive to a flash drive, are the saved files saved in the drive with a schema similar to the one that existed on the hard drive? Sorry I am being kind of lazy in not doing an experiment; thought someone may save me time...

http://constructionasphalt.tpub.com/TM-5-3895-374-24-1/css/TM-5-3895-374-24-1_666.htm consider the misalignment illustration in the link above. What makes a misaligned belt drive inefficient? I imagine it is due to increase friction but where does this friction manifest in the system? (which...

What is the situation for my hard drive now? Can I fix it with a software? Should I change it? The PC is working with no problem? What should I do now? Should I change the hard drive in the service? S.M.A.R.T status is bad. There was nothing a few days ago. I cannot understand how this has...

Long drive shaft of 5 inches fits into the end fitting and is rigidly attached by the bolts. Input torque is equal to output torque as we are ignoring losses from bearing. Let's assume that the load on the shaft is equal to 3*weight. (3 g's) (looking for more conceptual understanding rather...

What is innovation ? ... here is a great example. I'm in this field and know this product pretty well. I though it may be interesting to both the old and new PF members... http://www.controldesign.com/articles/2016/peter-hammond-recalls-the-birth-of-the-medium-voltage-drive/?show=all

If you were in a warp drive spaceship traveling at say 2c. Would all observers see your ship traveling at 2c?

I am a 66 y/o firefighter that competes in the Firefighter Combat Challenge. One of the evolutions requires the FF to use a Keiser Force Machine. This is a 160# beam on Teflon runners, 2 each 2" x 36", in a stainless still tray. Using a 9# shot hammer we have to drive the beam 5'. The problem...

Is that "normal" for a machine running Windows 10? I have a 120GB hard drive and 55.2GB is being used for System & Reserved. Seems high.

I have Ettus B210 and trying to add 1 line configuration file "/etc/security/limits.conf" which will allow UHD drive to set priority. So , I typed this command to edit file: gksudo gedit /etc/security/limits.conf and add: #@student hard nproc 20 #@faculty soft...

I just had this thought while watching a video about the EM drive...basically using 2 lasers to bounce them off prisms inside an object to push the craft through space at a small but constant acceleration...could someone explain why this would not work?...please see attached image :)