A world-class tennis player can serve a tennis ball at 130 mi/h mi/h (about 58 m/s m/s ). The length of a tennis court is 78 ft ft . Approximately how long does an opponent have to react from the instant the ball is served until the ball reaches the opponent?.

The time taken is  

Explanation:

From the question we are told that

  The  speed is  

   The  length of the tennis court

 Generally the time taken is mathematically represented as

=>        

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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