P410/P609 Homework Assignment #4 Due Tuesday, November 7, 2006 Problem 1 Complete Problem 4.6 parts a-d on page 93 of CSM. If you would like to use Mathematica to solve some or all of this problem, you are welcome to do so. Please note that in part (c) many students in the past have gotten confused computing the relaxation time. You can only find the amplitude at the turning points of the motion, i.e., where the velocity changes time. You can use turning points where the position is positive or negative. If you make a semilog plot of the absolute value of these positions vs time, you should find an exponential decay. Problem 2 Using Mathematica, find the value of the integral of the function sin(x)/x over the interval [0,5]. Problem 3 The local newspaper carried a story about jury selection for a trial. The paper stated: At a hearing Thursday in Owen County, Nardi denied a motion filed by defense attorneys David Colman and Elizabeth Cure to disqualify the jury panel. Colman and Cure observed that out of 80 potential jurors, only one was younger than 30. "Monroe County has a population of 120,000 people, of which between 30,000 and 40,000 are students at Indiana University," the motion stated. "A truly random jury-selection process for Monroe County should result in no fewer than 20 students from Indiana University." This might be a good time for a lawyer joke, but I will resist that temptation and ask you to analyze this situtation. a) Assuming that there are 120,000 people in Monroe county and 30,000 of those people are students at IU, what is the probability that a group of 80 randomly selected people would include fewer than 20 students? Note, if you had been among the people called for jury duty, you probably would have been excused from jury duty if you had pointed out the lawyer how stupid his statement was. (I got out of jury duty a couple of years ago when I told the laywer that he had just contradicted himself.) b) What is the probability if 40,000 of the 120,000 people, that there would be fewer than 20 students in a randomly selected group of 80 people? Note: I will be pleased if you can use Mathematica to solve this problem, but if you prefer another approach, that is also fine. If you have taken a course in statistical mechanics or a math course that covered combinatorics you should have the theoretical background for solving this problem. If not, come see me we can talk about drawers containing red socks and blue socks and how many ways we can pick socks from the drawer.