using System; using L=Science.Physics.GeneralPhysics; namespace Serway.Chapter08 { /// /// Example07: Motion on a Curved Track /// A child of mass m rides on an irregularly curved slide /// of height h = 2.00 m ,as shown in Figure 8.12 /// The child starts from rest at the top. /// (A) Determine his speed at the bottom, assuming no friction /// is present. /// v_f = 6.26 m/s /// (B) If a force of kinetic friction acts on child, /// how much mechanical energy does the system lose? /// Assume that v_f =3.00 m/s and m=20.0 kg /// \Delta E = -302 J /// public class Example07 { public Example07() { } private string result; public string Result { get{return result;} } public void Compute() { L.Mass m = new L.Mass(); m.kg = 20.0; L.Work W = new L.Work(); W.J = m.kg*L.Constant.AccelerationOfGravity*2.0; L.KineticEnergy Ki = new L.KineticEnergy(); Ki.J = 0.0; L.KineticEnergy Kf = new L.KineticEnergy(); Kf.VariableQ = true; L.FundamentalLaw.WorkEnergyTheorem(Ki,W,Kf); L.Velocity vf = new L.Velocity(m,Kf); result += vf.ToString()+"\r\n"; //(B) L.Velocity vpf = new L.Velocity(); vpf.Z = 3.0; L.KineticEnergy Kpf = new L.KineticEnergy(m,vpf); result += Convert.ToString(Kpf.J - Kf.J); } } } /* 6.26099033699941 +/- 0 i +0 +/- 0 j +0 +/- 0 k (m/s) -302 */