Respostas

2013-03-20T22:22:42-03:00

V=180Km/h=50m/s

d=150+200=350m <---- 200m do trem + 150m do tunel

 

t=\frac{d}{v}=\frac{350}{50}\\ t=7s

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2013-03-21T16:23:27-03:00

180km/h :3,6=50 m/s

50m/s=200m+150m/delta t
50m/s=350m/delta t
50 delta t=350
delta t=7 s

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