解: y=0.05cos(10Jt-4πx) 与y=Acos2mvt-2x)比较得 (1)A=0.05mV=5Hzx=0.5m Ly=0.5×5=25m/s (2)Lm=Aa=0.05×10m=0.5Tm/s am=A2=0.05×(10m)2=0.5m2m/s2 结束目录y = 0.05cos(10πt 4πx ) A =0.05m n =5Hz l =0.5m um =Aω=0.05×10π=0.5πm/s am =Aω2 0.05×(10π) 2 = =0.5π2 m/s2 u= ln =0.5×5=2.5m/s 解： n π l y = Acos(2 t π ) 2 与 x 比较得 (1) (2) 结束 目录