FIGURE EX2.32 shows the acceleration graph for a particle that starts from rest at t = 0 s. What is the particle's velocity at t = 6 s?

(II) Figure 2–42 shows the velocity of a train as a function of time.

(a) At what time was its velocity greatest?

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(II) A sports car accelerates approximately as shown in the velocity–time graph of Fig. 2–43. (The short flat spots in the curve represent manual shifting of the gears.) Estimate the car's average acceleration in

(a) second gear and (b) fourth gear. <IMAGE>

(II) Given v(t) = 25 + 18t, where v is in m/s and t is in s, use calculus to determine the total displacement from t₁ = 1.3 s to t₂ = 3.6 s.

(II) Figure 2–42 shows the velocity of a train as a function of time.

(b) During what periods, if any, was the velocity constant?

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