SOLUTION: A race driver has made a pit stop to refuel. After refueling, he starts from rest and leaves the pit area with an acceleration of 5m/s2, after 4s he enters the main speedway. At th

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Question 1031640: A race driver has made a pit stop to refuel. After refueling, he starts from rest and leaves the pit area with an acceleration of 5m/s2, after 4s he enters the main speedway. At the same instant, another car on the speedway travelling at a constant velocity of 75m/s overtakes and passes the entering car. The entering car maintains its acceleration. How much time is required for the entering car to catch the other car?
Please help I have tried everything of my knowledge, but I just can't get it right. Thank you in advance.

Answer by ikleyn(52786) About Me  (Show Source):
You can put this solution on YOUR website!
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A race driver has made a pit stop to refuel. After refueling, he starts from rest and leaves the pit area with an acceleration
of 5m/s2, after 4s he enters the main speedway. At the same instant, another car on the speedway travelling at a constant velocity
of 75m/s overtakes and passes the entering car. The entering car maintains its acceleration. How much time is required for the
entering car to catch the other car?
Please help I have tried everything of my knowledge, but I just can't get it right. Thank you in advance.
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Your equation is 

75*t = %285%2F2%29%2At%5E2+%2B+20%2At.   (1)

The left side is the distance covered for t seconds by the car moving uniformly with the speed of 75 m%2Fs. 

The right side is the distance covered for t seconds by the car moving with the constant acceleration 5 m%2Fs%5E2 with the initial speed of 20 m%2Fs = 4 s * 5 m%2Fs%5E2. 

Speed of 20 m%2Fs is the entering speed for the first car.

Solve (1) for t.