Below is a graph position vs time for a car. ст 5 Ꮖ 4 3 2 B C 1 0 A 1 2 -1 -2 -3 -4 100 5 07. 6 Ꭰ E + (a) For which segments is the car at rest? (b) For which segment is the velocity of the car greatest? (c) What is the average velocity of the car from A to E? (d) What is the average velocity of the car from C to D? (e) What is the instantaneous velocity of the car at 7.5s? (f) Draw the velocity vs time plot F 0 G t 10

A racing car starts from rest at t = 0 and reaches a final speed at time t. II the acceleration of the car is constant during this time, which of the following statements are true? (a) The car travels a distance t. (b) The average speed of the car is /2. (c) The magnitude of the acceleration of the car is /t. (d) The velocity of the car remains constant, (e) None of statements (a) through (d) is true.

Unreasonable Results (a) What is the final velocity of a car originally traveling at 50.0 km/h that decelerates at a rate of 0.400 m/s2 for 50.0 s? (b) What is unreasonable about the result? (c) Which premise is unreasonable, or which premises are inconsistent?

A hiker walks 3.00 km north and then 4.00 km west, all in one hour and forty minutes, (a) Calculate his average speed in km/h. (b) Calculate the magnitude of his average velocity. (See Section 3.2 and 3.3.)

An express train passes through a station. It enters with an initial velocity of 22.0 m/s and decelerates at a rate of 0.150 m/s2 as it goes through. The station is 210 m long. (a) How long is the nose of the train in the station? (b) How fast is it going when the nose leaves the station? (c) If the train is 130 m long, when does the end of the train leave the station? (d) What is the velocity of the end of the train as it leaves?

Colonel John P. Stapp, USAF, participated in studying whether a jet pilot could survive emergency ejection. On March 19, 1954, he rode a rocket-propelled sled that moved down a track at a speed of 632 mi/h. He and the sled were safely brought to rest in 1.40 s (Fig. P2.41). Determine (a) the negative acceleration he experienced and (b) the distance he traveled during this negative acceleration.

Physics Review A hockey player strikes a puck, giving it an initial velocity of 10.0 m/s in the positive x-direction. The puck slows uniformly to 6.00 m/s when it has traveled 40.0 m. (a) What is the pucks acceleration? (b) At what velocity is it traveling after 2.00 s? (c) How long does it take to travel 40.0 m? (See Section 2.5.)

The position of a particle moving along the x axis varies in time according to the expression x = 3t2 where x is in meters and t is in seconds. Evaluate its position (a) at t = 3.00 s and (b) at 3.00 s + t. (c) Evaluate the limit of x/t as t approaches zero to find the velocity at t = 3.00 s.

The Acela is an electric train on the Washington-New YorkBoston run, carrying passengers at 170 mi/h. A velocity-time graph for the Acela is shown in Figure P2.69. (a) Describe the train's motion in each successive lime interval, (b) Find the trains peak positive acceleration in the motion graphed, (c) Find the trains displacement in miles between t = 0 and t = 200 s.

A glider of length moves through a stationary photogate on an air track. A photogate (Fig. P2.19) is a device that measures the time interval td during which the glider blocks a beam of infrared light passing across the photogate. The ratio vd = /td is the average velocity of the glider over this part of its motion. Suppose the glider moves with constant acceleration. (a) Argue for or against the idea that vd is equal to the instantaneous velocity of the glider when it is halfway through the photogate in space. (b) Argue for or against the idea that vd is equal to the instantaneous velocity of the glider when it is halfway through the photogate in time. Figure P2.19