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Nutka1998 [239]

3 years ago

12

A train is moving with a velocity of 20 m/s. when the brakes are applied the acceleration is reduced to -0.6 m/s².calculate the

distance covered by the train before coming to rest

1 answer:

Serhud [2]3 years ago

3 0

Answer:

x = 333.33 [m]

Explanation:

To solve this problem we must use the following kinematics equation.

$v_{f}^{2} = v_{i}^{2}-(2*a*x)$

where:

Vf = final velocity = 0

Vi = initial velocity = 20 [m/s]

a = desacceleration = 0.6 [m/s^2]

x = distance [m]

Note: the final speed is zero as the body finishes its movement.

Now replacing:

0 = (20)^2 - (2*0.6*x)

1.2*x = 400

x = 333.33 [m]

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