document.write( "Question 1165530: An engineer in a locomotive sees a car stuck
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\n" ); document.write( "If the engineer’s reaction time is 0.22 s,
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Algebra.Com's Answer #851322 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "An engineer in a locomotive sees a car stuck on the track at a railroad crossing
\n" ); document.write( "in front of the train. When the engineer first sees the car, the locomotive
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\n" ); document.write( "If the engineer’s reaction time is 0.22 s, what should be the magnitude
\n" ); document.write( "of the minimum deceleration to avoid an accident?
\n" ); document.write( "Answer in units of m/s^2
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document.write( "In 0.22 of a second, the locomotive moves forward 29*0.22 = 6.38 meters.\r\n" );
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document.write( "The remaining distance to the car is 160 - 6.38 = 153.62 meters.\r\n" );
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document.write( "At the time moment t= 0.22 s, the locomotive starts decelerating.\r\n" );
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document.write( "We assume that the deceleration value remains constant.\r\n" );
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document.write( "At this condition, the average rate to the stop is  29/2 = 14.5 m/s.\r\n" );
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document.write( "Thus the time decelerating to the full stop is   = 10.59448276 seconds.\r\n" );
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document.write( "The uniform deceleration value is   = 2.737273792.\r\n" );
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document.write( "ANSWER.  The minimum uniform deceleration is about 2.74 m/s^2.\r\n" );
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