How Far Will a Uniformly Accelerating Train Travel Before Stopping?

AI Thread Summary
A train moving with uniform acceleration takes 20 seconds to travel 400 meters and 30 seconds for the next 400 meters. To determine how much farther it will travel before stopping, the initial velocity and acceleration need to be calculated using the equations of motion. Two equations can be set up: one for the first 400 meters and another for the total distance of 800 meters over 50 seconds. Solving these equations will yield the values for initial velocity and acceleration. This approach will help find the distance the train travels before coming to rest.
Phyzics J
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Can Someone help me with this constant acceleration problem?! pleasez

1. A train which is moving with uniform acceleration is observed to take 20s and 30s, respectively, to travel successive 400m. How much farther will it travel vefore coming to rest if the acceleration remains constant?



2. I tried to find the change in velocity between those time intervals by using the formula:
Velocity=change in displacement/time



The Attempt at a Solution

 
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Hi Phyzics J, welcome to PF.
Let vo be the initial velocity when you start observing the train.
Then use
s = vo*t -1/2*a*t^2 and write two equations. One for s = 400 m and t = 20 sand second for s = 400 + 400 = 800 m and t = 20 + 30 = 50 s.
Solve the two equations to find vo and a and proceed.
 


Thank you sooo much rl.bhat, I appreciate it :)
 
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