开关的种类很多,如果按同时有几个活动触头分,可分为单掷、双掷等类,但不管哪一类开关,在电路中都是起着使电路接通或断开的作用.由于开关的接通或断开,对电路的基本特征及用电器通过的电流和两端电压的影响,这在电路分析中是相当重要的.我从以 There are many kinds of switches. If there are several active contact points at the same time, they can be classified as single-throw or double-throw. However, no matter which kind of switch, it is in the circuit to make the circuit turn on or off. Due to the switching on and off of the switch, the basic characteristics of the circuit and the current through the appliance and the voltage across the two ends, this is very important in circuit analysis.