4. A bystander hears a siren vary in frequency from 592 Hz to 380 Hz as a fire truck approaches, passes by, and moves away on a straight street. What is the speed of the truck? (Take the speed of sound in air to be m/s

Bob has just finished climbing a sheer cliff above a level beach and wants to figure out how high he climbed. All he has to use is a baseball, a stopwatch, and a friend on the ground below with a long measuring tape. Bob is a pitcher and knows that the fastest he can throw the ball is about ?0=34.1 m/s.v0=34.1 m/s. Bob starts the stopwatch as he throws the ball, with no way to measure the ball's initial trajectory, and watches carefully. The ball rises and then falls, and after ?1=0.910 st1=0.910 s the ball is once again level with Bob. Bob cannot see well enough to time when the ball hits the ground. Bob's friend then measures that the ball hit the ground ?=123 mx=123 m from the base of the cliff. How high above the beach was the ball when it was thrown?

11.33

1. Consider a car that initially travels in the positive direction at a speed of 30 m/s. The car uniformly speeds up to 40 m/s in a time of 5 s. Find the following: a. The acceleration of the car. b. The distance traveled over the entire 5.0 seconds. C. The distance traveled during the 2 s interval where the clock goes from t = 2 s, to t= 4 s. (Assume the 5 s time interval begins with the time = 0s.)

3. The position of a pinewood derby car was observed at various times; the results are summarized in the following table. Find the average velocity of the car for (a) the first second, Answer (b) the last 3 s, and Answer (c) the entire period of observation. t (s) 1.0 2.0 3.0 4.0 5.0 æ (m) 2.3 9.2 20.7 36.8 57.5

Archibald, an aging geezer, is out bicycling one fine afternoon, reliving his glorious youth and oblivious to the world around him. As he approaches a busy intersection, a police officer directing traffic blows his whistle to get Archie’s attention so he’ll slow down and stop. But Archie doesn’t stop; he just speeds right through the intersection as if the traffic cop wasn’t even there. The cop radios one of his colleagues and gets her to stop the old geezer. She gives him a traffic citation for failing to heed the command of a police officer directing traffic. When the case gets to traffic court, Archie explains to the judge that he didn’t hear the officer’s whistle because he is going deaf and cannot hear frequencies above 3000 Hz. The traffic cop informs the judge that his standard issue police whistle emits a frequency of 2100 Hz and he has a certificate to prove it. Thinking quickly (at least for an old geezer) Archie says that it may be true that the police whistle emits a sound…

Rachel watches a thunderstorm from her window. She sees a flash of lightning bolt and begins counting the seconds until she hears a clap of thunder 10.0 ??????? later. Assume the speed of sound in air is 340 ?⁄? and the light was seen instantaneously. How far away was the lightning?

ANALYSIS III Data Set 3. Imagine that you are on Mars and have done the following experiment: a small ball is held about 10 meters above the surface and is released from rest and allowed to fall freely. A motion detector placed below the ball records the position- time data shown in the data table at the right. Assume that air friction is so small that it can be neglected in your analysis. Note that the position decreases with time because the ball is falling toward the detector.

Time Position Velocity 0 0   0.05 0.08 1.6 0.1 0.17 1.7 0.15 0.26 1.73333333 0.2 0.35 1.75 0.25 0.459 1.836 0.3 0.59 1.96666667 0.35 0.73 2.08571429 0.38 0.9144 2.40631579   Velocity vs time What is the acceleration of the ball independently for each component of the motion as a function of time? What is the acceleration of the ball for:             When it is thrown             When it is caught/lands Magnitude at its highest point?   What are the Launch Velocity and velocity of the highest point for the velocity vs time graph?             Is this value reasonable?

Consider the motion described by the figure below.   (a) Find the displacement at t = 12.4 s(b) Find the displacement at t = 12.9 s(c) Find the displacement at t = 16.5 s