#Pdf basics of electricity portable#

Resistance in a circuit can also be helpful when needing to alter voltage levels, current paths, etc. The light bulb introduces enough resistance in a circuit to heat up the filament inside, causing light to be emitted. The most common application for resistance in a circuit is the light bulb. When electrons flow against the opposition offered by resistance in the circuit, friction occurs and heat is produced.

Electrical resistance, measured in Ohms, is the measure of the amount of current repulsion in a circuit. This leaves us with the letter R which represents Resistance. As mentioned previously, current is the measurement of the flow of charge in a circuit. The next component of Ohm’s law is current, the units of which are Amperes in the formula, current is represented by the very logical choice of the letter I. In the field, you might hear the term “common grounds” which refers to each device in a system using the same zero-point reference (or ground) to ensure the same potential difference ( or voltage) is applied throughout the system. Normally the two points will be +10V and 0V (also known as ground), but it can also be the difference between +5V and -5V, +20V and +10V, etc. When we see a value such as 10 Volts, it is a measurement of the potential difference between two reference points. In other words, it is a measurement of the work required to move a unit charge between two points.

The V is for voltage, which means the potential difference between two charges.

The most fundamental law in electricity is Ohm’s law or V=IR.

#Pdf basics of electricity portable#

Therefore today, most portable devices use DC power while power plants produce AC. With AC it is possible to produce the high voltages needed for long transmissions. Nikola Tesla changed all that with the invention of alternating current electrical systems. But as societies grew the use of DC over long transmission distances became too inefficient. Thomas Edison and Alessandro Volta were pioneers in DC current and wrote much of electricity’s history. DC is current that flows in one direction with a constant voltage polarity while AC is current that changes direction periodically along with its voltage polarity. There are two types of current, direct current (DC) and alternating current (AC). This flow of electrical charge is referred to as electric current. No matter how the charge is created, chemically (like in batteries) or physically (friction from socks and carpet), the movement of the discharge is electricity. So what is electricity and where does it come from? More importantly, why is carpet, socks and a doorknob a bad combination? In its simplest terms, electricity is the movement of charge, which is considered by convention to be, from positive to negative. Read on to discover more about basic electrical theory. From talkies to eight tracks to screaming “I want my MTV”, even hashtagging, none of it would be possible #WithoutElectricity. For an example, imagine where the medical field would be without electricity and in that sense how many lives have been saved due to electrical devices like defibrillators, pacemakers, etc. Electricity is everywhere it lights our way, cooks our food and can even brush your teeth. No single discovery has affected our lives, our culture and our survival more than electricity.