Motion in a Straight Line Linear Motion at Consta CHAPTER 2 2-2 Acceleration 10 Find the position and velocity 2.00 s if the particle is initially p of 20.0 m/s and experiences a tude 4.00 m/s, directed west. II An elevator is initially moving upwas 12.00 m/s. The elevator experiences a 60 A sprinter starts from rest and accelerates to 10,0 m/s in a time interval of 1.00 s. Find the magnitude and direction of the runner's average acceleration a during this interval. Problems (listed by sectionns) Suppose that beginning of of 0.100 m/s (a) How long Acceleration in One Dimension 2-1 2A girl swims the length of a pool and back in 30.0 s. The pool is 20.0 m long, and the girl's speed is con- Unit C (a) Find the magnitude and direction (b) How far did it move during the 3 of 30.0 m/s before her parachute ward acceleration of magnitude 10 m aw Length I in254 I cm 03 It 30.5 1 m 3.28 I mi 528 1 km 0.6 1A 10 I LY 94 (b) What wo ,480 (a) Compute her speed v and her average velocity v. (b) When is her acceleration not equal to zero? 3 A world champion drag racer starts from rest and ac- final velocity, A ball is thr locity of 15 distance of celeration, A fullback stant opens, she experiences celeration of 75.0 m/s2. (a) If this acceleration remained c (a) Find the racer's average velocity ū, in m/s. (b) The car's speed at the end of the strip is 402 km/h (250 mi/h). Find the average acceleration ā, in rest and a an upward v ball just E quarter-mile drag strip in 5.80 s. time would be required to reduce the speed to a safe 5.00 m/s? (Actually tion is not constant in this case, bu sume tha Volume L-10 t' 0.0 n' 10 celerates over a during th of 8.00 m constas 4 A football player carrying the ball runs straight ahead at the line of scrimmage and directly into a wall of de- fensive linemen. The ball carrier has an initial speed of 8.00 m/s and is stopped in a time interval of 0.200 s. Find the magnitude and direction of his aver- behind i of constant acceleration provide an e A block m/s me (b) How far does the paratrooper fall du rest and 5.00 m interval? ates at 13 The brakes are applied to a cax trave level highway. A typical value for the m the car's acceleration is 5.00 m/s. f the speed is 30.0 m/s, how long does it take how far does it travel, starting from the tion), 5 A baseball player hits a line drive. Just before the ball is struck, it is moving east at a speed of 40.0 m/s (90 mi/h). Just after contact with the bat, 1.00 × 10-3 s later, the ball is moving west at a speed of 50.0 m/s (112 mi/h). Find the ball's average acceleration. 6 A car moves along a straight section of highway. Its speedometer readings at 1.0 s intervals are 50 km/h at 1 = 0, 54 km/h at t = 1.0 s, 56 km/h at t = 70 km/h at t= 3.0 s. the ble A cyc initia age acceleration. at the Find brakes are applied? celer 14 A human being cannot tolerate accelera ous permanent injury. If the acceleration A sp more than a few hundred m/s? without for more than a few seconds, the maxim imu 2.0 s, (a) acceleration is much less. Suppose a cas moving at 30.0 m/s and then is quickly (a) Find the magnitude of the average acceleration ā in m/s?, over the 3.0 s interval. (b) Estimate the instantaneous acceleration, in m/s², at (b) collision. (a) What is the minimum time over which 2-3 7 At 0.100 s intervals, the x coordinates of a particle are 0, 1.01 cm, 2.05 cm, and 3.12 cm. Estimate the instan- taneous velocity and acceleration at t = 0. 8 A Ferrari F40, the world's fastest production car, can start from rest and achieve an average acceleration of 6.70 m/s² over a 4-second interval. How fast is the car moving after 4.00 s? 9 Find the constant acceleration of a particle whose ve- locity changes by 3.00 m/s every 0.100 s. must be decelerated in order that he no an acceleration of magnitude (b) What is the minimum distance the drie greater 10 m/s2? Assume constant acceleration allowed to move forward during the deu (Air bags are an improvement over cause the distance the driver moves f greater with a compressible air bag than belt. This does not mean, however, the want to move forward in the car wite Why not?)