We can store electrical energy in to metal plates seperated by an insulating medium .We call such a device a capacitor,or a condenser,and its ability to store electrical energy capacitance.It is measured in farad.

• 两片绝缘的金属板之间能够存储一定的电量，我们称这种装置为电容器，它的功能就是具有一定的电容量，其衡量单位是法拉。