using System; using L=Science.Physics.GeneralPhysics; namespace Serway.Chapter17 { /// /// Example05: The Broken Clock Radio /// Your clock radio awakens you with a steady and /// irritating sound of frequency 600 Hz. One morning, /// it malfunctions and cannot be turned off. In frustration, /// you drop the clock radio out of your fourth-story /// dorm windows, 15.0 m from the ground. Assume /// the speed of sound is 343 m/s. /// (A) As you listen to the falling clock radio, what frequency /// do you hear just before you hear the radio striking /// the ground? /// f' = 571 Hz /// (B) At what rate does the frequency that you hear change /// with time just before you hear the radio striking /// the ground? /// df'/dt = -15.5 Hz /// public class Example05 { public Example05() { } private string result; public string Result { get{return result;} } public void Compute() { L.Frequency f = new L.Frequency(); f.Hz = 600.0; double s = 15.0; double g = L.Constant.AccelerationOfGravity; L.Speed vs = new L.Speed(); vs.mPERs = -g*Math.Sqrt(2.0*s/g); L.Frequency fo = new L.Frequency(); fo.VariableQ = true; L.Speed vo = new L.Speed(); L.Sound sound = new L.Sound(); sound.DopplerEffect(f,vs,fo,vo); //(A) result+=Convert.ToString(fo.Hz)+"\r\n"; //(B) L.Calculus.Function func = new L.Calculus.Function(vel); double ans = L.Calculus.Differentiation(func, Math.Sqrt(2.0 * s / g)); result+=ans.ToString(); } private double vel(double t) { return 600.0*(343.0+0.0)/(343.0+9.8*t); } } } //571.434238648089 //-15.549385195665