电子元器件英语PPT介绍.pptVIP

Basic Concepts of Circuit Theory 电路理论的基本概念 殷聪聪 电子0911 voltage and current Voltage and current are vital to understanding electronics, but they are quite hard to grasp because we cannot see them directly. 电压和电流 电压和电流对于电子学的理解是非常重要的，但是由于它们不可以直接观察到，因而掌握它们是非常困难的。 Voltage is sometimes described as the push or force of the electricity,it isnt really a force but this may help you to imagine what is happening. It is possible to have voltage without current, but current cannot flow without voltage. 电压有时被描述成电流的推动力，事实上电压并不是一个力，但这种描述能够帮助你更好的理解电压是怎么回事。没有电流电压可以单独存在，但没有电压就不可能存在电流。 Voltage Voltage is a measure of the energy carried by the charge.Strictly：voltage is the“energy per unit charge”. 电压是对电荷所带能量大小的一个衡量。严格的讲：电压表示“每单位电荷的能量”。 The proper name for voltage is potential difference or p.d. for short,but this term is rarely used in electronics. 电压的准确名称是电势或简称为p.d,但在电子学中很少使用这个名称。 Voltage is supplied by the battery(or power supply） 电压由电池（或电源）提供。 Voltage is used up in components,but not in wires. 电压将被消耗在元件上，而不是导线上 Voltage is across a component. 电压存在于元件两端。 Voltage is measured with a voltmeter,connected in parallel. 电压应并联在电路中的电压表来测量。 Voltage At a Point and Zero volts 某一点上的电压和零电压 Voltage is a difference between two points,but in electronics we often refer to voltage at a point meaning the voltage difference between that point and a reference point of 0v（zero olts) 电压是指两点间的一个电势差，但在电子学中我们经常提到的某一点上的电压其实是指这点和零电压参考点之间的电势差。 Zero volts could be any point in the circuit,but to be consistent it is normally the negative terminal of the battery or power supply.You will often see circuit diagrams labelled with 0v as a reminder. 电路中的任何一点都可为零电压点，但为了保持一致我们常把电池或电源的负端作为零电压点。你经常会看到电路图中标有0v字样的提示。 Current Current is the rate of flow of charge. 电流是电荷流动的速率。 Current is not used up,which flows into a component must flow out. 电流不会被消耗掉，电流流进一个元件后还必须流出。