ELECTRICITY IES Río Cabe 1) ELECTRICITY AND MATTER. Mª Covadonga Yugueros 1.1. Conductor and insulators Valbuena 1.2. How to obtain electricity 1.3. The transport of electric energy 1.4. Effects of electric current 2)Electric quantities 2,1. Electric current 2.2. Voltage 2.3. Resistance. 3) Ohm's law 4)Electric circuits 4.1. Components of an electric circuit 4.2. Representation and symbols. 5)Types of circuits. 5.1. Series circuits 5.2. Parallel circuits 5.3. Series-parallel combination circuits
2,Electric quantities The basic electric quantities or variables are
Current Intensidad de corriente
Variables
Voltage or potential difference Voltaje o tensi贸n
Resistance Resistencia
2.1. Electric current What is the intensity of traffic?
How can we measure it?
Electrons
In electricity, which are moving
Electric current (I) is the amount of electrons flowing through a conductor for a time
-
-
-
little current
-
-
-
-
-
-
-
-
-
A lot of current
-
Electric current II Electric current is represented by the letter It is represented:
Its unit of measurement (SI)
Amperes or Amps
A
Amperio
Es la intensidad que circula por un punto de un conductor cuando por ĂŠl pasa un culombio de carga en un segundo.
1 Ampere
1 Coulomb
6.240.000.000.000.000.000 electrons
To measure the current we use the ammeter AmperĂmetro
2.2. Voltage o Potential difference For a flow of current there must be a different energy level between two points of the circuit: One point with a high number of electrons and the other with a low number. This difference between the electrical energy at two points in a circuit is called Voltage.
The amount of energy that a battery is able to supply electrons the force that causes a current to flow
Voltage
Voltage o Potential difference II Voltage is represented by the letter
Its unit of measurement (SI)
Volts Voltios
To measure the current we use the Voltmeter VoltĂmetro
It is represented:
V
2.3. Electric resistance The resistance is the opposition of the components of a circuit to the flow of electric current.
Electric resistance is represented by the letter
Its unit of measurement (SI)
Ohm
It is represented:
Ohmio
Conductors
Low resistance
Materials Insulators
High resistance
立
Electric Resistance II
ge a im e h nt o ck i l C
material
The resistance of an element depends on Length
More legth
More Resistance
-
Less length Less Resistance
Section More Section
Less Section
-
-
-
- -
-
More Resistance
-
-
-
Less Resistencia
clic k
Electric variables
3. Ohm's law
Voltage Current
The three electric quantities
Resistance The relationship between current, voltage and resistance was discovered by George Simon Ohm in SXIX : Ohm's law
Ohm law: Voltage in a circuit is directly proportional to the current flowing and to the resistance that exists. Link 1 V I
Link 2 R