关于电容器充电和放电的问题,用能量观 点解答时,应注意是否有电能损失以及损失多 少电能. 1.电容器的充电 (1)磁场中的滑杆运动给电容器充电时, 杆减少的机械能全部转化为电能. 例1 两根平行导轨竖直放置,上端接有 电容器,电容为C.一根金属棒可沿导轨滑动, 接触良好,不计摩擦和电阻,其质量为m.两导 Regarding the problem of capacitor charging and discharging, when using the energy point of view, pay attention to whether there is power loss and how much energy is lost. 1. Charging of the capacitor (1) When the slider motion in the magnetic field charges the capacitor, the reduced mechanical energy of the rod is converted. For power. Example 1 Two parallel guide rails are placed vertically with a capacitor connected to the top and the capacitor is C. A metal rod can slide along the guide rails. The contact is good, excluding friction and resistance. Its mass is m.