Everyone knows from experience what an electric current is, but not everyone understands the physical nature of this phenomenon, especially if physicists were not interested in this during the school course. And for many students, physics textbooks seem slurredly written. Let's try to correct these errors by describing this phenomenon simply.
Collective farm in work
The word "current" itself indicates that we are talking about movement, and not about a static phenomenon. What is electric current? This is simply the directional movement of charged particles in a conductor or electrolyte. Classic conductors are objects made of metals. They are always considered dangerous, remember this if you need to push the victim away from the current source. The nature of electric current in metals is associated with a special property of matter. The fact is that the electrons in metals are quite free and represent something like a collective economy. Therefore, substances of this category carry out current very easily; it is easy to achieve directed motion of particles.
Events in Solutions
Electric current is also well transmitted by solutions of charged particles - ions. Moreover, positively charged cation particles approach the cathode, the negative electrode, and anion particles whose charge is negative, approach the anode. Thus, a solution with negative and positive ions, that is, with electrolytes, is a good current conductor.
Why variable?
Types of electric current - so often the question is formulated on the exam. And in response, as a rule, they want to hear: “constant or variable”. What is the difference? Direct current moves in the same direction, alternating current changes its direction. Why did we need alternating current (namely, it is supplied in domestic services and in production?). The fact is that when using AC, there is much less loss when transferring it via cable. Thus, the transmission of electricity becomes more economical.
Electricity and Magnets
What is electric current in nature? He was seen by everyone who saw lightning - a current of monstrous tension and strength. Man uses many properties of the current, for example, the ability to provoke magnetic phenomena: in inductors, motors and generators. It is to the work of scientific researchers that we owe the comfort of modern life.
Northerners see more
What is electric current for a resident of the northern countries? This is the reason for the northern lights, a very spectacular natural phenomenon. Another natural example of electric current can be considered the so-called solar wind, which, strictly speaking, is the cause of the northern lights. This is a stream of particles from the corona of the sun. He also creates magnetic storms. This flow is normal for the Sun, but some people constantly feel these phenomena on themselves.
Electric current is also capable of causing thermal phenomena. Simple heating of working appliances is proof of this. And this is not only about appliances designed for heating, such as a boiler and heater. Side effect - heating from electric current - is very common.
For many decades, electric current has faithfully served man. But you have to be very careful with him. We pay tribute to hundreds of lives for electricity, every year many people die due to negligence. The current does not forgive mistakes!