Here I'm going to explain electronics. I will have projects posted on the projects page where u can practice making circuits on a breadboard.
Electricity
Electricity is an essential ingredient of matter.
Electrons have a NEGATIVE electrical charge. Protons have a POSITIVE electrical charge. Neutrons have NO electrical charge.
Ions- Normally an atom has an equal number of electrons and protons. The charges cancel to give the atom NO net electirical charge. It's possible to dislodge one or more electrons from most atoms. This causes the atom to have a net positive charge. It's then called a POSITIVE ION. If a stray electron combines with a normal atom, the atom has a net negative charge and is called a NEGATIVE ION.
Electrons- FREE electrons can move at high speeds through metals, gases, and vacuum, or they can rest on a surface. Many trillions of electrons can rest on a surface or travel through space or matter at near the speed of light (186,000 miles per second)!
Resting Electrons- A group of negative electrons on a surface causes the surface to be negatively charged. Since the electrons are not moving, the surface can be said to have a NEGATIVE STATIC ELECTRICAL CHARGE.
Moving Electrons- A stream of moving electrons is called an ELECTRICAL CURRENT. . Resting electrons can quickly form an electrical current if placed near a cluster of positive ions. The positively charged ions will attract the electrons which will rush in to fill the "holes" or voids left by the missing electrons.
Missing Electrons- Mechanical friction, light, heat or a chemical reaction may remove electrons from a surface. This causes the surface to be positively charged. Since the positively charged atoms are at rest, the surface can be said to have a POSITIVE STATIC ELECTRICAL CHARGE.
Static Electricity
You generate static electricity every time you warlk across a carpet, pull tape from a roll, remove your clothing or dry clothes in a drier. Much of the time you don't even realize it unless the air is dry and the static charge suddenly crackles, pops and flashes is way to a new home. These static charges are caused by MECHANICAL FRICTION.
Direct Current (DC) Electricity
An Electrical current can flow in either of two directions through a conductor, If it flows in only one direction, whether steadily or in pulses, i's called DIRECT CURRENT (DC). It's important to be able to specify the quantity and power of a Direct current. Key Terms:
Current (I- Current is the quantity of electrons passing a given point. The unit of current is the ampere. One amperee is 6,280,000,000,000,000,000,000 electrons passing a point in one second.
Voltage (V or E)- Voltage is electrical pressure or force. Voltage is sometimes referred to as POTENTIAL. VOLTAGE DROP is the difference in voltage between the two ends of a conductor through which curren is flowing. If we compare current to water flowing through a pipe, then voltage is the water pressure.
Power (P)- The work performed by an electrical current is called power. The unit of power is the WATT. The power of a direct current is its voltage times its current.
Resistance (R)- Conductors are not perfect. They resist to some degree the flow of current. The unit of resistance is the OHM. A potential difference of one volt will force a current of one ampere through a resistance of one ohm. The resistance of a conductior is its voltage drop divided by the current flowing through the conductor.
OHM'S LAW-
V = I x R
I = V / R
R = V / I
P = V x I
From "Getting Started in Electronics" by Forrest M. Mims III----------------Pictures by me :)
If a stray electron combines with a normal atom, the atom has a net negative charge and is called a NEGATIVE ION.
Resting electrons can quickly form an electrical current if placed near a cluster of positive ions. The positively charged ions will attract the electrons which will rush in to fill the "holes" or voids left by the missing electrons.