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2 years ago

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Find deacceleration An engineer in a locomotive sees a car stuck on the track at a railroad crossing in front of the train. When

the engineer first sees the car, the locomotive is 360 m from the crossing and its speed is 16 m/s. If the engineer’s reaction time is 0.53 s, what should be the magnitude of the minimum deceleration to avoid an accident? Answer in units of m/s^2

1 answer:

earnstyle [38]2 years ago

3 0

Answer:

The deceleration is $a = -0.7273 \ m/s^2$

Explanation:

From the question we are told that

The distance of the car from the crossing is $d = 360 \ m$

The speed is $u = 16 \ m/s$

The reaction time of the engineer is $t = 0.53 \ s$

Generally the distance covered during the reaction time is

$d_r = u * t$

=> $d_r = 16 * 0.53$

=> $d_r = 8.48 \ m$

Generally distance of the car from the crossing after the engineer reacts is

$D = d- d_r$

=> $D = 360 - 8.48$

=> $D = 352 \ m$

Generally from kinematic equation

$v^2 = u^2 + 2as$

Here v is the final velocity of the car which is 0 m/s

So

$0^2 = 16^2 + 2 * a * 352$

=> $a = -0.7273 \ m/s^2$

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