Solve Kinematics Problem: High Speed Train & Locomotive

AI Thread Summary
The discussion revolves around a kinematics problem involving a high-speed train and a stationary locomotive. The train is traveling at 161 km/h and needs to decelerate to avoid a collision with the locomotive, which is 676 meters ahead and moving at 29 km/h. The user initially calculated the required deceleration as -1.43 m/s² but was informed that the correct value is 0.93 m/s². Participants suggest focusing on the relative speed of the train to the locomotive and applying the appropriate kinematics formulas to solve for the deceleration. The conversation emphasizes understanding the relationship between the two speeds and the distance to determine the correct answer.
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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