Electric charge is a property of all objects and is responsible for electrical phenomena
Matter is everything that has mass and occupies space. All matter is composed of atoms.
Atoms are made up of smaller particles. An atom has two parts: nucleous ans shell
· Nucleous: Protons (+ charge) and neutrons (have no charge) are fixed in the nucleus (don´t move)
· Shell: electrons (- charge) move around the nucleus
Matter is neutral: number of positive charges (protons) is equal to the number of negative charges (electrons). But... sometimes, there is a movement of electrons from one material to another. This generates static electricity (charges are at rest)
Two objects with the same charge repel each other. Two objects with different charge attract each other.
Materials can be:
· Conductors: are materials that allow electric current to pass through them (silver, copper…)
· Insulators: are materials that don´t allow the current to pass through them (plastic, wood…)
Electric current is a continuous movement of electrons (to produce it must be an imbalance of charges between two points). There are two types:
· DC (direct current): electrons always move in the same direction. It has a constant value. For example the current generated by batteries (1,5 V; 4,5V; 9V; 12V…)
· AC (alternating current): electrons change constantly the direction of movement. It´s the electricity that we use at home, at schools… (in Spain 220V)
Electric circuit: is a set of connected components through which an electric current circulates. main components are:
generators (battery…)
wire conductor (cable…)
receptor (bulb, motor, buzzer, resistor…)
control elements (switch…)
and protection elements (fuse…)
STUDY the table of components!!!!!
STUDY how to do draw a circuit and its diagram!!!!!