Train Definition and 638 Threads

  1. M

    Inertia: Jumping in a Moving Train - Results?

    if you are in a moving train and jump from your position(on the same plane),will you land in the same place where you jumped? train is moving as well as you. frankly,i did jump and see ,since i fell down i could not find out!
  2. N

    Calculating Force Exerted by a Moving Train on a Track

    Hey I was hoping some would be able to help me or show me how to calculate the amount of force a train exerts on a spot on a track. Simply I could calculate the force exerted on a spot of the track as the weight of the train in kgs times the gravity (9.8m/s^2) will give me netwons of force...
  3. D

    Train Collision: Will They Meet? Find Out!

    Homework Statement Two trains are heading towards each other on the same track. They are initially 2100 feet apart. The first train has an initial velocity of 88 ft/s due East, the second train has an initial velocity of 107 ft/s due West. Both trains begin decelerating at a rate of a =...
  4. B

    Epicyclic Gear Train Homework: Why Does $\omega_3=\omega_6$?

    Homework Statement http://img8.imageshack.us/img8/2393/geartain.jpg The Attempt at a Solution I got the right answer, by assuming that \omega_3=\omega_6 , but i don't know why this has to be so. Here's my working: \frac{\omega_2-\omega_3}{\omega_4-\omega_3}=-\frac{N_4}{N_2}...
  5. B

    Solving Circular Motion: Train Slows from 90 to 50 km/h

    Homework Statement 1. Homework Statement A train slows down as it rounds a sharp horizontal turn, slowing from 90.0 km/h to 50.0km/h in that 15.0s that it takes to round the bend. The radius of the curve is 150m. Compute the acceleration at the moment the train speed reaches 50.0 km/h...
  6. B

    Five train cars and their final speed

    Homework Statement Three identical train cars, coupled together, are rolling east at 1.13 m/s. A fourth car traveling east at 6.43 m/s catches up with the three and couples to make a four-car train. A moment later, the train cars hit a fifth car that was at rest on the tracks, and it couples...
  7. R

    Stopping a Train: Calculating Time from Velocity

    Homework Statement I have a distance versus velocity graph that gives me the braking distance for a train (for known gradients of track - but gradient is irrevelant for my problem). the graph has distance on the vertical axis and velocity on the horizontal axis. What i want to know is that for...
  8. T

    Making a Magnetic Levitation Train

    I would like to make a maglev train for a physics project, but I would prefer it to be simple and for the most part easy to make, as I do not have access to too many supplies. Hopefully, you can help me generate a list of possible ideas with brief explanations on how to construct them and how...
  9. D

    Compound gear train problem (WHY IS IT SO HARD )

    Compound gear train problem (WHY IS IT SO HARD!) Homework Statement http://img5.imageshack.us/img5/1663/problemw.jpg I need to calculate the angular acceleration of the fan at 2600 RPM (motor speed) depicted by figure 4. Homework Equations Sum(torques with respect to input) =...
  10. S

    Train and Speed of Sound in Air versus Track

    Homework Statement Stan and Ollie are standing next to a train track. Stan puts his ear to the steel track to hear the train coming. He hears the sound of the train whistle through the track 3.1 s before Ollie hears it through the air. How far away is the train? (Use 5,790 m/s as the speed...
  11. V

    Ball dropped from a moving train

    Can anybody please explain why the ball dropped from a moving train appears to take a parabolic path w.r.t the frame of reference of a person standing at the platform? Thanks
  12. N

    Portable radio in train, bad reception

    Hi, I travel by train nearly every day, and I am using a crappy portable radio connected to my phone (it's just a very small radio receiver built into the earphones) to listen to the radio during the journey. I can't help but noticing two effects, one that can probably be explained pretty...
  13. H

    Impulse Train vs Sampling Function

    How come these two functions are used interchangebly? A sampling function is supposed to be a square wave with a very small duty cycle, but at least the height is still finite. A delta function has infinite height and zero width. It seems like both square wave and dirac train are used as...
  14. J

    How Does Light Behave on a Rotating Disc in Different Reference Frames?

    Suppose one constructs a thought experiment similar to the famous light beam bouncing around a train car. In this experiment a laser and mirror are attached to the surface of a rotating disc such that the beam is sent through the center of the disc. From my understanding of the train experiment...
  15. Q

    Find the constant acceleration of the train

    Homework Statement Liz rushes down onto a subway platform to find her train already departing. She stops and watches the cars go by. Each car is 8.60 m long. The first moves past her in 1.50 s and the second in 1.10 s. Find the constant acceleration of the train. Homework Equations...
  16. T

    Riding a train from Chicago to Detroit

    Homework Statement You're riding in a very fast train from Chicago to Detroit. In Chicago you set your watch to the correct time, but as you ride through downtown Detroit, you notice that your watch differs from the time shown on the clocks in the station! Are all the clocks in Detroit...
  17. J

    What is the Speed of the Train as it Rounds a Curve?

    Homework Statement A train traveling at a constant speed rounds a curve of radius 218 m. A lamp suspended from the ceiling swings out to an angle of 16.6° throughout the curve. What is the speed of the train? Homework Equations mv^2/r The Attempt at a Solution I drew a...
  18. Gokul43201

    Drunk person loses leg to passing train

    What would you have awarded the plaintiff if you were on the jury (and why)? Presumably, the medical (and other related) expenses came up to ~$3.6 million. Or does that include things like "psychological damage"? (I have no idea) More here...
  19. M

    Rain from the perspective of a moving train and a gun on the moon

    question(s): These are questions from an exam i took earlier tonight, but do not know if i got them correct. 1) Rain is falling with velocity 30 m/s at an angle of 60° from the vertical and is blowing due east. If a passenger inside of a train (also traveling due east) observes the rain...
  20. J

    Train Moving pulling two boxcars

    Homework Statement A train consists of a 4000 kg locomotive pulling two loaded boxcars, the first with a mass of 12,000 kg and the second with a mass of 16,000 kg. Assume that the boxcar wheels roll without friction and ignore aerodynamics. The acceleration of the train is 0.4 m/s2. With...
  21. P

    Train station Probability help

    Homework Statement Eighty per cent of all scheduled trains through Roma Street station arrive on time. If 10 trains go through the station every day, find: a the probability that at least 8 trains are on time b the probability that at least 8 trains are on time for 9 out of the next 10...
  22. J

    Calculating Train Speed Increase: 1.5x10^7 kg Train

    Homework Statement A frieght train has a mass of 1.5x10^7 kg. The wheels of the locomotive push back on the tracks with a constant net force of 7.5X10^5N, so the tracks push forward on the locomotive with a force of equal magnitude. (ignore aerodynamics and friction) how long would it take...
  23. S

    What Deceleration Prevents a Train Collision?

    Homework Statement When a high-speed passenger train traveling at 158 km/h rounds a bend, the engineer is shocked to see that a locomotive has improperly entered onto the track from a siding and is a distance D = 699 m ahead. The locomotive is moving at 27.2 km/h. The engineer of the...
  24. B

    Lose weight (mass) or train? - effect of losing weight (mass) on power

    Lose weight (mass) or train? -- effect of losing weight (mass) on power I'm having troubles wrapping my head around this one (I've provided the example from my class notes below): My question -- how does a decrease in the mass of the rider increase his power producing ability by 18 W...
  25. B

    Answer: Lose Weight or Train? Power Increase Explained

    EDIT -- I posted this here because I figured its more of a conceptual problem than a HW problem, but if people see otherwise, feel free to delete the post. I'm having troubles wrapping my head around this one (I've provided the example from my class notes below): My question -- how does a...
  26. matt_crouch

    Can a Fly Stop a Train? Analyzing Newton's 3rd Law

    Me and some friends where down the pub and an interesting idea came up. say a fly is flying and collides with an on comming train then the train and the fly at an instant must stop? how can this be? I am trying to think of a way of analysing this. this is my guess. according to Newtons...
  27. L

    The Georgia 300 - Obama Inauguration Train Car

    Background on The Georgia 300 http://news.yahoo.com/s/ap/20090116/ap_on_go_pr_wh/inauguration_rail_car Originally named the General Polk for a http://en.wikipedia.org/wiki/Leonidas_Polk" . http://community.webshots.com/photo/fullsize/2357037130001227466LPcdUK...
  28. wolram

    News Scientists jumping off the warming train

    http://epw.senate.gov/public/index.cfm?FuseAction=Minority.Blogs&ContentRecord_id=2158072e-802a-23ad-45f0-274616db87e6 POZNAN, Poland - The UN global warming conference currently underway in Poland is about to face a serious challenge from over 650 dissenting scientists from around the globe...
  29. matt_crouch

    Train goes through a tunnel your ears pop a little?

    how come when a train goes through a tunnel your ears pop a little? is it due to the pressure increasing? or are my ears just weird :smile:
  30. J

    Moving Train Problem: Help & Advice Needed

    Hi, Can anybody offer any assistance with the following problems please: 1. A train is moving along a straight line at constant speed V. Inside a carriage an object is thrown upwards from a height h (measured from the floor of the carriage) with initial velocity v. Determine the trajectory...
  31. L

    Is Jane Morally Obligated to Intervene in Train Dilemmas?

    A. Jane is standing at a railway switch as an oncoming train rapidly approaches from the left. Just beyond her is a fork in the track. Five innocent people, unaware of the train, are standing on the left fork. One innocent man is standing on the right. If Jane does nothing, the train will veer...
  32. C

    Can Animals Teach Humans? The Surprising Intelligence of Pets

    Many people think of animals as stupid and capable of learning only through conditioning without the ability to make creative leaps. My question is are there any instances where an animal has tried to train a human successfully? Most human would be to blithe to even entertain the notion that...
  33. J

    Maximum Compression of buffers for a Train

    Homework Statement I need to work out the maximum compression of buffers for a train with 1.2kg mass, traveling at 0.45m/s and the spring constant, k, is 4.8x10^3 Nm^-1 Homework Equations I tried using 1/2kx^2 but I don't know if I am doing it right The Attempt at a Solution I...
  34. J

    Nonuniform circular motion toy train

    Homework Statement a toy train rolls around a horizontal 1.0m diameter track. the coeffifient of rolling friction is 0.10 a. what is the magnitude of the train's angular acceleration after it is released b. how long does it take the train to stop if it's released with an angular speed of...
  35. T

    Circular motion of a train magnitude and angle

    Homework Statement A train is rounding a circular curve whose radius is 2.00 X 10_{}2 m. At one instant, the train has an angular acceleration of 1.50 X 10^-3 rad/s_{}2 and an angular speed of 0.0400 rad/s. (a) Find the magnitude of the total acceleration (centripetal plus tangential) of the...
  36. T

    Stability of Drink and Bottle on Train Table

    Homework Statement You are riding in a train and have just opened a bottle of beer. Prove that for your bottle to be as stable as possible on the table (which is shaking), you should drink sufficient beer such that the surface of the beer coincides with the centre of gravity of the...
  37. L

    How Does Train Acceleration Affect Projectile Firing Angle for Maximum Distance?

    A cannon on a train car fires a projectile to the right with speed v relative to the train, from a barrel elevated at angle theta. The cannon fires just as the train, which had been cruising to the right along a level track with speed vt, begins to accelerate with acceleration a. Find an...
  38. P

    Prove that the flange of a train wheel moves backwards in respect to the ground

    Prove that the flange of a train wheel moves backwards in respect to the ground, using the trigonometric functions, linear and angular velocity I really have no idea to go about doing this, all I know is that the proof involves some use of trigonometric functions, linear and angular velocity
  39. S

    A train traveling at a constant speed

    Homework Statement A train traveling at a constant speed rounds a curve of radius 200 m. A chandelier suspended from the ceiling swings out to an angle of 17.0° throughout the turn. What is the speed of the train? I am confused about the orientation of the chandelier to the turn and how...
  40. P

    How Can Uniform Acceleration and Velocity Affect Train Travel Times?

    Homework Statement A train is instructed to start at rest at station 1 and accelerate uniformly between points A and B, then coast with a uniform velocity between points B and C, and finally accelerate (slowing down) uniformly between points C and D until the train stops at station 2. The...
  41. 1

    Opent top freight train with coal

    Question 3 text A freight car moves along a frictionless level railroad track at constant speed. The car is open on top. A large load of coal is suddenly dumped into the car. What happens to the velocity of the car? Question 3 answers It increases. It remains the same. It decreases...
  42. K

    A fast fly hits a train and then ?

    If a fly were flying very fast, perhaps .5c, and it struck a train, what would probably happen? A red-hot little fly hole through the train? A dent and a spray of fly plasma? A slow moving train? Something else? Ignore air resistance, and consider the train to be a series of 3cm steel...
  43. P

    Solving Bullet Train Speed Change Problem

    I need some help with this question: Two people, who are traveling on a bullet train between Tokyo and Kyoto, are willing to tolerate acceleration magnitudes as large as 0.2 g. The driver wants to change speeds from 250 to 300 km hr-1 on a curved piece of track. If the radius of curvature...
  44. E

    Tangential and radial train acceleration

    Homework Statement A train slows down as it rounds a sharp horizontal turn slowing from 90.0 km/h to 50.0km/h in the 15 s that it takes to round the bend. The radius of the curve is 150 m. Compute the acceleration at the moment the train speed reaches 50km/h. Assume it continues to slow down...
  45. H

    Angular acceleration of a pendulum on an accelerating train

    If I hang a pendulum on the ceiling of an accelerating train (with an initial angular displacement), how would the angular acceleration be affected? My intuition told me that the angular acceleration of the pendulum should be affected by the acceleration of the train. But...whether the...
  46. D

    Four trains coupling - find speed of resulting train

    Three identical train cars, coupled together, are rolling east at 4 m/s. A fourth car traveling east at 6 m/s catches up with the three and couples to make a four-car train. What is the speed of the four-car train? I have no idea what to do. Please Help...thanks in advance :)
  47. H

    Acceleration of a Train Problem

    Homework Statement A train slows down as it rounds a sharp horizontal turn, slowing from 90.0 km/h to 50.0km/h in that 15.0s that it takes to round the bend. The radius of the curve is 150m. Compute the acceleration at the moment the train speed reaches 50.0 km/h. Assume that it continues...
  48. jtbell

    Don't text while driving a train

    http://www.cnn.com/2008/US/09/15/train.collision/index.html
  49. L

    How Are Superconductors Revolutionizing Maglev Train Technology?

    Hello, I have a problem connecting an answer to the question Describe how superconductors and the effects of magnetic fields have been applied to develop a maglev train. I have the information on the superconductors, but i don't have the information of the maginetic field how it is applied. I...
  50. K

    Train Crash Kills 25 in LA: A Tragic Story

    http://www.newsday.com/news/nationworld/nation/la-me-traincrash13-2008sep13,0,245095.story" Man, this is really terrible. The last time I remember something like this happening was when some guy left his car on a Metrolink track. A sorry example of physics at work :(.
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