Solve Kinematics Problem: High Speed Train & Locomotive

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SUMMARY

The kinematics problem involves a high-speed train traveling at 161 km/h and a locomotive moving at 29 km/h, with a distance of 676 meters separating them. The engineer must calculate the necessary deceleration of the train to avoid a collision. The correct deceleration is determined to be 0.93 m/s², contrasting with an incorrect calculation of -1.43 m/s². The key to solving this problem lies in applying the appropriate kinematics formulas while considering the relative motion of the train and the locomotive.

PREREQUISITES
  • Understanding of kinematics equations, specifically for uniformly accelerated motion.
  • Knowledge of relative velocity concepts in physics.
  • Familiarity with units of measurement in physics, particularly converting km/h to m/s.
  • Basic algebra skills for solving equations.
NEXT STEPS
  • Study the kinematics equations, particularly the formula for distance under constant acceleration.
  • Learn how to convert speeds from km/h to m/s for accurate calculations.
  • Explore relative motion problems to better understand how to analyze moving objects in the same direction.
  • Practice similar physics problems involving deceleration and collision avoidance scenarios.
USEFUL FOR

Students studying physics, particularly those focusing on kinematics, as well as educators looking for examples of motion problems involving deceleration and relative velocity.

Nenad
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Hello everyone, this problem may seem simple to all of you, but I seem to be having a mental block. My physics prof assigned some review last class and I seem to be stuck on this problem.

Here goes:
When a high speed train traveling at 161km/h rounds a bend, the engineer see that there is a locomotive lying on the track directly ahead of the moving train. The locomotive is traveling at 29.0km/h in the same direction as the train, and is 676m away when the train sees it. The engineer of the high speed trian imeediatelly applyes the brakes.
(a) that must be the decelleration of the train in order not to hit the locomotive. (friction is neglected).

Ive tried setting distance traveled of the two events equal to each other, and I keep getting a decelleration of -1.43m/s^2, but the answer is 0.93m/s^2. A helpfull hint on how to approach the problem would be fantastic.
Awaiting a reply, Thanks.
 
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First of all, your answer your answer for a will be negative, but the answer to the question should be positive because they ask for the decelleration.

If they are traveling in the same direction, the speed of the train with respect to the locomotive is ____ (pretent the locomotive is stationary). The distance is 676 m. What kinematics formula applies to this? Now solve for a.
 
thanx man.
 

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