Acceleration. linear motion. i'm stuck

AI Thread Summary
The discussion centers on calculating the deceleration of a train that moves at an initial velocity of 60 m/s and stops after traveling 600 meters. The initial attempt used the formula v = s/t, which is incorrect due to the non-uniform velocity. Participants suggest using the kinematic equation v² - u² = 2as to find acceleration, where v is the final velocity, u is the initial velocity, and s is the displacement. The correct approach involves substituting the known values into this formula to solve for deceleration. This method provides a clear pathway to the solution.
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acceleration. linear motion. I'm stuck!

Homework Statement


a train moves at a velocity of 60 m s-1 and stops after a distance of 600m. what is its deceleration?

Homework Equations


v=s/t

The Attempt at a Solution


this is my working:
u= 0 m s-1
v= 60 m s-1
s= 600 m

v=s/t
60=600/t
t=10 s

...and I'm stuck here. please help!
 
Last edited:
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The velocity is not uniform. So you can't use v = s/t. And here initial velocity is 60 m/s and final velocity is 0. Use appropriate kinamatic formula which relates initial velocity, final velocity , acceleration and displacement.
 


what formula? tell me and i'll try to work it out!
 


v^2 - u^2 = 2as
 


My favorite for finding acceleration is a(\Deltax)=(1/2)(\DeltaV2)
 
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