Solving Train Collision: Min Rate, Collision Speed & Distance Traveled

  • Thread starter Thread starter ts21121
  • Start date Start date
  • Tags Tags
    Collision Train
Click For Summary
SUMMARY

The discussion centers on calculating the minimum deceleration required for a passenger train traveling at 30 m/s to avoid colliding with a freight train moving at 5.9 m/s, positioned 336 m ahead. The minimum constant deceleration determined is 0.887 m/s², based on the engineer's reaction time of 0.36 seconds. For a longer reaction time of 0.79 seconds, the approach speed of the passenger train at the moment of collision needs to be calculated, along with the distance traveled during the reaction time. The equations of motion used include x = x₀ + v₀t + 1/2 at² and v = v₀ + at.

PREREQUISITES
  • Understanding of kinematics, specifically equations of motion.
  • Knowledge of basic physics concepts such as speed, distance, and acceleration.
  • Familiarity with the concept of reaction time in relation to motion.
  • Ability to perform calculations involving constant acceleration and deceleration.
NEXT STEPS
  • Review the derivation of the equations of motion, particularly x = x₀ + v₀t + 1/2 at².
  • Study the impact of reaction time on stopping distances in high-speed scenarios.
  • Explore advanced kinematic problems involving multiple objects in motion.
  • Investigate real-world applications of deceleration rates in train safety systems.
USEFUL FOR

Physics students, engineers in transportation safety, and professionals involved in railway operations and safety analysis.

ts21121
Messages
3
Reaction score
0
A passenger train is traveling at 30 m/s when the engineer sees a freight train 336 m ahead of his train traveling in the same direction on the same track. The freight train is moving at a speed of 5.9 m/s.

1.If the reaction time of the engineer is 0.36 s, what is the minimum (constant) rate at which the passenger train must lose speed if a collision is to be avoided?

2. If the engineer's reaction time is 0.79 s and the train loses speed at the minimum rate described in Part (a), at what rate is the passenger train approaching the freight train when the two collide?


For both reaction times, how far will the passenger train have traveled in the time between the sighting of the freight train and the collision?

x=x0+v0t +1/2 at2
v=v0+at



The Attempt at a Solution


for part 1 i know the answer is .887m/s^2.
after this i am completely lost on how to solve for part 2 and 3
 
Physics news on Phys.org
Hi ts21121, welcome to PF.
I am getting slightly different answer for the part 1. Will you show your calculations?
 

Similar threads

1-dimensional kinematics - final velocity of 2 trains in opposing direction
  • · Replies 3 ·
Replies
3
Views
1K
Train collision (linear kinematics)
  • · Replies 6 ·
Replies
6
Views
2K
Kinematics involving two objects
  • · Replies 3 ·
Replies
3
Views
2K
A passenger train is traveling at 27 m/s when the engineer s
  • · Replies 4 ·
Replies
4
Views
2K
Deceleration necessary to prevent a train collision
  • · Replies 2 ·
Replies
2
Views
2K
Deceleration of Train to Avoid Collision
  • · Replies 1 ·
Replies
1
Views
4K
Train Collision Problem - Calculating Head Start
  • · Replies 1 ·
Replies
1
Views
4K
AP Physics 1 kinematics problem
  • · Replies 1 ·
Replies
1
Views
2K
Two decelerating trains on a collision course
  • · Replies 2 ·
Replies
2
Views
2K
Train chase: collision avoidance
  • · Replies 5 ·
Replies
5
Views
2K