动能Wk=2m2 =mAo sin (ot+p) 势能=1 W 2 kA2cos2(ot+φ 总能W=W+W mv2+x2 (A) 2 守恒!势 能 kA cos ( t ) 21 kx 21 W 2 2 2 p =  +  = mA sin ( t ) 21 mv 21 W 2 2 2 2 k =   +  动 能 = 总 能 2 2 2 2 k p m ( A ) 21 kA 21 kx 21 mv 21 W W W = =  = + = + 守恒！ -1 -0.5 0.5 1 0.2 0.4 0.6 0.81 x Wk Wp W 2 4 6 8 10 12 -0.2 0.2 0.4 0.6 0.81 Wp Wk x t 4