Train Definition and 638 Threads

Homework Statement A train which weighs 1.4406E4N hit a car with a mass of1470kg. The cars skids 15m at angle of 68° to the crossing and the coefficient of friction between the tyres and the road is 0.25. Find the initial velocity of the car entering the crossing. Homework Equations...

3. Two train cars are to be coupled on the tracks. One of the cars, say A is initially at rest. The other car, say B is traveling at a speed v toward A: Car B is empty, whilst car A is full of pig iron and has a mass of 102mB: After coupling, the two cars travel a distance of 20 meters before...

It might seem to be a stupid question..But I really want to figure it out so I posted it here. Again, the problem should be familiar to anyone here. Two lightning bolts strike at both end s of a moving train simultaneously (according to the stationary observer). My question is: In the...

I have a gear train system where i have 3 gears meshing with each other (different sizes) gear A, B and C. Gear B is my input/driver and gears A and C are my output/driven. If i know the input RPM and input torque for gear B, what are the gear ratios/the amount of torque transmitted to gear A...

Hello guys, so I had a homework and I couldn't understand the point of my teacher. The question goes like this: http://desmond.imageshack.us/Himg3/scaled.php?server=3&filename=21976607.jpg&res=medium So the question is, "Calculate the voltage drop over the TRAIN when it is at the...

Hi all, i have a question relating to the period of pendulum. I got this question: A bob of mass 0.5 kg is suspended by a string from the ceiling inside a train moving on a straight level rail (to the right). If the train has an acceleration of 0.2g, what is the tension in the string when the...

Can you explain Einstein's train metaphor/thought experiment. Thanks

Please refer to the attached diagram The train moves in the direction B-A If the events seen in the ground observer simultaneously, it should be seen at A before B in the train In special case, the difference in times between A and B according to the train observer could be equal to the...

Consider Problem #1 here. The author seems to assume that the train comes immediately when one of the friends gives up on waiting for the other. What if the train arrival times follow a Poison process with rate λ? I have some ideas but I won't post anything in case anyone else wants a stab at it.

Homework Statement Hello fellow Physics Forumers My first post and , hopefully not my last. I've been lurking for a long while and the tempo has increased since I started my 1st year engineering course last semester. So I decided to register today as I have a bit of a puzzle. We have a...

Homework Statement A woman is riding a bicycle at 18.0 m/s along a straight road that runs parallel to and right next to some railroad tracks. She hears the whistle of a train that is behind. The frequency emitted by the train is 840 Hz, but the frequency the woman hears is 778 Hz. Take the...

hi, i have some problems in power train calculations for a small race car has a chain instead of crank shaft converting motion to the rear side, calculating torque on the axle and wheels, forces and the acceleration of the car. So, can anyone help or mention a guide reference ? thank you

Kinematics Train Crash Question Homework Statement A passenger train is behind a freight train, both on the same set of tracks and moving in the same direction. The freight train is moving at a constant speed of 27. 0 m/s and maintains that speed. The passenger train is originally moving at...

How do you Train in physics when you have LITTLE previouse education! HI, I'm a 27 year old guy from the u.k, I have little previous education apart from my G.C.S.E's from when i was 16. A few years ago i stumbled across quantum physics and after constant research online i discovered that not...

Hi all :) I was thinking earlier about if people are born a genius or they become a genius due to the way they think. I consider the hardest thing in the world to learn is math / physics and almost every genius or extremely smart people always excel in these fields. I am terrible at maths and...

Suppose I´m right in the middle of a train and suddenly bright light bolts out of both ends of my train. I swear that I saw both bolts of light at exactly the same time. Later I saw historical evidence of the char marks at the ends of my train. Although my train seemed stationary to me, an...

Hi If you are on a train moving at the speed of 100km east and you fire a bullet west at 100km, do the bullet move away from the spot it was fired from or does it just drop to the ground? Just a brain teaser that has been annoying me. Would it just drop to the ground as the speed of the...

two trains approach each other at 60m/s the gap between them is 120 m. A bird on one train flies to the other in 120m/s. The bird flies back again. But how many trips would the bird do before the trains crash? thx

Homework Statement A locomotive accelerates a 24-car train along a level track. Every car has a mass of 50000 kg and is subject to a frictional force f = 250 v, where the speed v is in meters per second and the force f is in Newtons. At the instant when the speed of the train is 28 km/h...

Can anyone tell me what will happen to a length og a rod if it is measured in a running train and why?

[b]1. A person standing close to a railroad crossing hears the whistle of an approaching train. He notes that the pitch of the whistle drops as the train passes by and moves away from the crossing. The frequency of the distant approaching whistle is 555 Hz; it drops to 472 Hz after the train is...

Homework Statement What is the tractive force F necessary between subway car A and the track to reach a speed of 100km/h in 1 minute? What distance was traveled during this time? At this point the brakes are fully applied on the wheels of car A in order to slow the train to 40km/h. The...

Homework Statement Find the speed at which Superman (mass=89.0 kg) must fly into a train (mass = 17755 kg) traveling at 85.0 km/hr to stop it. Running into the train at that speed would severely damage both train and passengers. Calculate the minimum time Superman must take to stop the...

Homework Statement A passenger is standing without slipping in a forward accelerating train. The coefficient of static friction between the feet and floor is 0.47 a) Draw an FBD for the passenger in Earth's frame of reference b)Draw an FBD for the passenger in the train's frame of reference...

Hello everyone, thanks for reading. So, this is pretty basic, but unfortunately I'm not sure of the answer - A fly is flying in a train, in the air, but isn't moving (one of these static-annoying flies). Then the train starts moving. The fly would then be seen to people sitting on the...

I've got an answer to a question but I'm not sure if it's correct as i don't have the answers. A roller coaster train is propelled at 57m/s and towards a vertical part of track which has a height of 139m, what is the velocity of the roller coaster train when it reaches the top of the tower...

Homework Statement We have an observer moving along a moving train car with speed v (assumed to be relative velocity between observer and car). Two light signals are emitted from each end of the car. a)Where is the observer if he sees both signals simultaneously? b)From his point of view...

Homework Statement You are in a train traveling on a horizontal track and notice that a iece of luggage starts to slide toward the front of the train. from this observation you can conclude that this train is not an inertial reference frame because it is slowing down. Homework Equations...

A train is traveling up a 4.4 incline at a speed of 3.10 when the last car breaks free and begins to coast without friction. How long does it take for the last car to come to rest momentarily? The way I approached it that I reduced the speed to its x and y components. But I don't know what...

A ball is hanging from a long string that is tied to the ceiling of a train car traveling eastward on horizontal tracks. An observer inside the train car sees the ball hang motionless. Draw a clearly labeled free-body diagram for the ball if the train has a uniform velocity. i drew two...

The problem statement, all vaA ball is hanging from a long string that is tied to the ceiling of a train car traveling eastward on horizontal tracks. An observer inside the train car sees the ball hang motionless. Draw a clearly labeled free-body diagram for the ball if the train has a...

allright, I'm finishing up my final Gymnasium physics course and the weirdest chapters (QM and Einstein) are at the end. So here is a book-example I don't understand: Lightning strikes at point A and B at the same time (if an outside observer is watching). Between A and B is a train moving at...

Good day folks, I hope someone can help me. How do I calculate w(1) without a w(arm)? There is no fixed gear, so no w(gear) = 0 as per normal, which has me baffled. Also - how do I calculate the overall gear ratio? Regards.

A few months ago I was surfing idly and found this little thing called a Gravity Train. For those who do not know what it is, see http://en.wikipedia.org/wiki/Gravity_railroad" . After reading about it I thought maybe I should try and find out how much time it would take (42.2 minutes) but...

I am researching for a sci-fi screenplay that I am writing for fun. To keep bone density from losing the estimated 1.5% per month on Mars I want to simulate Earth gravity by having the colonists live aboard condominiums that are fitted with a rail car suspension and travel in a perfect circle in...

in einstein train thought experiment, if two bulbs were placed, in the front and rear of a moving train. And a person A with a single switch for the two bulbs stands in the middle of the train. Near the lights are clocks which register current time, when the light glows. would the person A...

In the design of a rapid transit system, it is necessary to balance the average speed of a train against the distance between stops. The more stops there are, the slower the train's average speed. To get an idea of this problem, calculate the time it takes a train to make a 6.0 trip in two...

I have seemed to confuse myself after watching this video: Everything makes sense except for the bit where the video says the passenger sees the bolts at different times. How can this be justified and how do we know the passenger doesn't see them at the same time from his frame of reference?

How if the small RC helicopter Hover at inside center of the train . the train is moving constant velocity. will the helicopter moving backward?

1. Hi, I am currently doing a project which the main objective is to build an miniature Maglev Train Prototype and compare its performance with a Conventional Train. 2. I am having a big problem in the propulsion system of the Meglev Train which is the long stator linear synchronous...

Homework Statement A train is traveling at 3.73 degree incline at a speed of 3.25 m/s, when the last car breaks free and begins to coast without friction. (i) How long does it take for the last car to come to rest momentarily? (ii) How far did the last car travel before (momentarily)...

if train moves at speed of light the passenger will do any work with very less speed as time becomes slow. why this happens?

If travelers sat on connected lawn chairs on wheels guided by rails pulled by a motor on wheels we might reduce the ratio of rail train weight to that of the weight of passengers carried. An Amtrak passenger train weighs about 200,000 lbs. and holds say 100, 200 lb. people, for a ratio of...

If you throw a tennis ball straight up in a moving train, the ball will drop back down on the same spot so you can catch it right? Does this happen because i am in a closed space where the air is still? What would happen if i went on top of the train (so i guess the roof of the train) and did...

...having to call out the name of this station.

Homework Statement An engineer in a locomotive sees a car stuck on the track at a railroad crossing in front of the train. When the engineer first sees the car, the locomotive is 250 m from the crossing and its speed is 12 m/s. If the engineer’s reaction time is 0.36 s, what should be...

A train leaves the train station at 9:00 am and travels at a constant speed of vt = 65 km/hr on a straight track. At 10:30 am, a car leaves the same train station and travels in the same direction at vc = 115 km/hr on a road next to the train track. a.How far from the station is the place...

Dear All, In the http://galileoandeinstein.physics.virginia.edu/lectures/srelwhat.html" , there is one assumption I don't understand. Why do we assume that the distance w between the mirrors is constant for both the observer in the train and the observer outside the train? We could also let...

Hi, I was reading the book "Spacetime Physics" by Taylor/Wheeler. In their discourse on the relativity of simultaneity, the example they have used is Einstein's Train Paradox. See and also the attachment for the Train Paradox. My question is this: The analysis of what the train observer(TO)...

Homework Statement A gear ratio is req from A/D of 1:100 and that it will be necessary to redesign D so that it has 100 teeth. Determine: a)number of teeth on c b)number of teeth on planet gears. This followed on from another question. An epicyclic gear c is the annulus and is fixed. The...