(III) Mary and Sally are in a foot race (Fig. 2–46). When Mary is 22 m from the finish line, she has a speed of 4.0 m/s and is 5.0 m behind Sally, who has a speed of 5.0 m/s. Sally thinks she has an easy win and so, during the remaining portion of the race, slows down at a constant rate of 0.40 m/s² to the finish line. What constant acceleration does Mary now need during the remaining portion of the race, if she wishes to cross the finish line side-by-side with Sally? <IMAGE>

Figure 2–55 shows the position vs. time graph for two bicycles, A and B.

(c) At which instant(s) are the bicycles passing each other? Which bicycle is passing the other?

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(III) A fugitive tries to hop on a freight train traveling at a constant speed of 5.0 m/s. Just as an empty box car passes him, the fugitive starts from rest and accelerates at a = 1.4 m/s² to his maximum speed of 6.0 m/s, which he then maintains.

(b) What is the distance traveled to reach the box car?

(II) Two locomotives approach each other on parallel tracks. Each has a speed of 155 km/h with respect to the ground. If they are initially 9.5 km apart, how long will it be before they reach each other? (See Fig. 2–39.)

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Figure 2–55 shows the position vs. time graph for two bicycles, A and B.

(e) Which bicycle has the larger average velocity? <IMAGE>

(III) Mary and Sally are in a foot race (Fig. 2–46). When Mary is 22 m from the finish line, she has a speed of 4.0 m/s and is 5.0 m behind Sally, who has a speed of 5.0 m/s. Sally thinks she has an easy win and so, during the remaining portion of the race, slows down at a constant rate of 0.40 m/s² to the finish line. What constant acceleration does Mary now need during the remaining portion of the race, if she wishes to cross the finish line side-by-side with Sally? <IMAGE>

A police car at rest is passed by a speeder traveling at a constant 36 m/s. The police officer takes off in hot

pursuit, accelerating at a constant 2.00 m/s². (a) How long does it take for the police officer to overtake the speeder? (b) Calculate the speed of the police car at the overtaking point.