A 22000 kg subway train initially traveling at 10.0 m/s slows to a stop in a station and then stays there long enough for its brakes to cool. The station’s dimensions are 65.0 m long by 20.0 mwide by 12.0 m high.
Question
A 22000 kg subway train initially traveling at 10.0 m/s slows to a stop in a station and then stays there long enough for its brakes to cool. The station’s dimensions are 65.0 m long by 20.0 mwide by 12.0 m high.
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General Physics
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Answer ( 1 )
Mass of train=22000kg
Velocity=10m/s
Kinetic energy of train=(1/2)*22000*10²=1100000 Joules
Volume of air=65*20*12=15600 m³
Density of air=1.2 kg/m³
Mass of air=15600*1.2=18720 kg
18720*1020*(change in temperature)=1100000
Change in temperature=1100000/(18720*1020)=0.058 K