图示为一平面简谐波在t=0时刻的波形图,则P处质点的振动方程为:y(m)u=0.08 m/sx(m)P/O 0.20 0.40 0.60 -0.04 A. y=0.04cos (0.4pi -3div 2pi ). B. y=0.04cos (0.4pi -1div 2pi ) C. y=0.04cos (0.4pi (3)div 2pi ). D. y=0.04cos (0.4pi (1)div 2pi ).

图示为一平面简谐波在t=0时刻的波形图,则P处质点的振动方程为:y(m)u=0.08 m/sx(m)P/O 0.20 0.40 0.60 -0.04

• A. $$ y=0.04\cos (0.4\pi -3\div 2\pi ). $$
• B. $$ y=0.04\cos (0.4\pi -1\div 2\pi ) $$
• C. $$ y=0.04\cos (0.4\pi {3}\div 2\pi ). $$
• D. $$ y=0.04\cos (0.4\pi {1}\div 2\pi ). $$