2. 1D Motion / Kinematics

The position-time graph for a moving box is shown below.

(a) What is the box's average velocity from 0 to 5s?
(b)What is the box's average velocity from 0 to 8s?
(c) What is the box's velocity in the interval where it's moving fastest?

The position-time graph for a ball on a track is shown below.

(a) What is the ball's velocity at 4s?

(b) At what time(s) is the ball approximately travelling at -10m/s?

(c) From t = 3 to 7s, what is the sign of the acceleration?

A cat walks in a straight line, which we shall call the $x$-axis, with the positive direction to the right. As an observant physicist, you make measurements of this cat's motion and construct a graph of the feline's velocity as a function of time (Fig. E$2.30$). Assuming that the cat started at the origin, sketch clear graphs of the cat's acceleration and position as functions of time.

A cat walks in a straight line, which we shall call the $x$-axis, with the positive direction to the right. As an observant physicist, you make measurements of this cat's motion and construct a graph of the feline's velocity as a function of time (Fig. E$2.30$). Find the cat's velocity at $t=4.0$ s and at $t=7.0$ s.

A physics professor leaves her house and walks along the sidewalk toward campus. After $5$ min, it starts to rain, and she returns home. Her distance from her house as a function of time is shown in Fig. E$2.10$. At which of the labeled points is her velocity decreasing in magnitude?

A physics professor leaves her house and walks along the sidewalk toward campus. After $5$ min, it starts to rain, and she returns home. Her distance from her house as a function of time is shown in Fig. E$2.10$. At which of the labeled points is her velocity constant and negative?

A physics professor leaves her house and walks along the sidewalk toward campus. After $5$ min, it starts to rain, and she returns home. Her distance from her house as a function of time is shown in Fig. E$2.10$. At which of the labeled points is her velocity constant and positive?

A physics professor leaves her house and walks along the sidewalk toward campus. After $5$ min, it starts to rain, and she returns home. Her distance from her house as a function of time is shown in Fig. E$2.10$. At which of the labeled points is her velocity zero?

A block is suspended from a spring, pulled down, and released. The block's position-versus-time graph is shown in FIGURE P2.38. Draw a reasonable velocity-versus-time graph.

(II) The position of an object along a straight tunnel as a function of time is plotted in Fig. 2–40. What is its average velocity

(c) between t = 0 and t = 5.0 s

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(II) The position of an object along a straight tunnel as a function of time is plotted in Fig. 2–40. What is its instantaneous velocity at t = 10.0 s?