<PRE><B>Question 1053209</B>
A train was traveling at 15m/s and sped up to 30 m/s over a distance of 1600m. What was its acceleration?
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Average speed for 1600 meters was (15+30)/2 = 22.5 m/sec
Time to move 1600 m at 22.5 m/sec = 1600/22.5 = 640/9 seconds
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Accel = (30-15)/(640/9) = 27/128 m/sec/sec
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Check:
s = vt + at^2/2
= 15*(640/9) + (27/256)*(640/9)^2
= 3200/3 + 1600/3
= 1600 meters</PRE>