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When train a, a high speed train, traveling with an initial unknown speed rounds a bend, the engineer is shicked to see another train, train b, on the track 400 meters in front of train a and heading towards train a; the two trains are heading towards eachother. train a instantly applied the breaks causing the train to decelerate at 1m/s/s; however, train b continued with the same speed of 3m/s. if train a was able to come to a stop just as train b collided into itdetermine the initial velocity of train a.

User Alioza
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Final answer:

The initial velocity of train A before applying the brakes and coming to a stop just as train B collided with it was approximately 28.28 m/s.

Step-by-step explanation:

To determine the initial velocity of train A, we can use the kinematic equation for uniformly accelerated motion:

v2 = u2 + 2as

Where v is the final velocity (0 m/s since train A stops), u is the initial velocity (what we're trying to find), a is the acceleration (-1 m/s2 because the train is decelerating), and s is the distance (400 meters).

Rearranging the formula to solve for u gives:

u = sqrt(v2 - 2as)
= sqrt(0 - 2(-1)(400))
= sqrt(800)
= 28.28 m/s (approximately)

Therefore, the initial velocity of train A was approximately 28.28 m/s.

User Glez
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