s16-1 LC Circuit LC Oscillations 振荡电路电磁振荡 1. LC circuit As shown in Fig. 17-1, the circuit consists of an inductor L and a capacitor C, which can produce an electric field and magnetic field varying with the time K charge C C q
§16-1 LC Circuit & LC Oscillations 振荡电路 电磁振荡 1. LC circuit As shown in Fig.17-1, the circuit consists of an inductor L and a capacitor C, which can produce an electric field and magnetic field varying with the time. L C L C K q0 q0 charge
2. LC Oscillations C and L: charge, electric field electric potential, electric q current, magnetic field …AL C are varying with the time. The resulting oscillations of the capacitors electric field and the inductors magnetic field are said to be electromagnetic oscillations. Such a circuit is said to oscillate Assume that 1=0, g=o at t=0. In the following, we will study this circuit in detail
2. LC Oscillations L C q C and L: charge, electric field, I electric potential, electric current, magnetic field,….. All are varying with the time. The resulting oscillations of the capacitor’s electric field and the inductor’s magnetic field are said to be electromagnetic oscillations. Such a circuit is said to oscillate. Assume that I=0, q=q0 at t=0. In the following, we will study this circuit in detail
Qualitatively I=0 0 maX cTIT I C 40 q B q=0 t=0 I=0 0 C qo 反向充电
Qualitatively: L C q0 I 0 t=0 I q L C q 0 max I L C I 0 q0 q0 q0 I q 反向充电
Qualitatively(定性): q=0 C了℃ C I=0 10 q max t=Th2 反向 I=0 qo C 复原 qo q
Qualitatively(定性）: L C 0 q I 0 t=T/2 I q L C q 0 max 0 I q I q 反向 L C I 0 q0 q0 复原
Quantitatively(定量): 电能口磁能电能→磁能白周期性变化 △U L dt q L △UC d 4=0 L—+ LC +Oy=0与谐振子的运动方程相似:q+x
Quantitatively（定量）: 电能 磁能 电能 磁能 周期性变化 L C q I i U dt dI L C q U i 0 C q dt dI L LC 1 dt dq I 与谐振子的运动方程相似：qx