2. 1D Motion / Kinematics

Figure 2–42 shows the velocity of a train as a function of time. At what time was its velocity greatest?

On a $v-t$ graph, which segment indicates that the object's velocity is decreasing?

Which pair of sentences describes the same velocity? (A) An object moves at $10m/s$ to the right. (B) An object moves at $-10m/s$ to the left. (C) An object moves at $10m/s$ to the left. (D) An object moves at $-10m/s$ to the right.

On a $v-t$ graph, which feature indicates that a runner is moving at a high speed?

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$2.30$). What is the cat's acceleration at $t=3.0$ s? At $t=6.0$ s? At $t=7.0$ s?

FIGURE EX2.12 shows the velocity-versus-time graph for a particle moving along the x-axis. Its initial position is at x₀ = 2 m at t₀ = 0 s. What are the particle's position, velocity, and acceleration at t = 1.0 s?

On a $v-t$ graph, what does a flat horizontal line indicate about the motion of an object?

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.

High-speed motion pictures ($3500$ frames/second) of a jumping, $210–μg$ flea yielded the data used to plot the graph in Fig. E$2.54$. (See 'The Flying Leap of the Flea' by M. Rothschild, Y. Schlein, K. Parker, C. Neville, and S. Sternberg in the November $1973$ Scientific American.) This flea was about $2$ mm long and jumped at a nearly vertical takeoff angle. Use the graph to answer this question: Find the flea's acceleration at $0.5$ ms, $1.0$ ms, and $1.5$ ms.

In a $v-t$ graph where time is measured along the $x$-axis, what physical quantity is measured along the y-axis?

(II) Figure 2–42 shows the velocity of a train as a function of time. When was the magnitude of the acceleration greatest?

High-speed motion pictures ($3500$ frames/second) of a jumping, $210–μg$ flea yielded the data used to plot the graph in Fig. E$2.54$. (See 'The Flying Leap of the Flea' by M. Rothschild, Y. Schlein, K. Parker, C. Neville, and S. Sternberg in the November $1973$ Scientific American.) This flea was about $2$ mm long and jumped at a nearly vertical takeoff angle. Use the graph to answer this question: Find the maximum height the flea reached in the first $2.5$ ms.

On a $d-t$ graph, why does a curved line indicate that the object is accelerating?

For a ball thrown straight upward, what are the velocity and acceleration of the ball at the highest point in its path?