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Electricity

In this article we will study about Electric current and circuit: Electric potential and potential difference, Ohm’s law etc.

Electricity is a form of energy and is a phenomenon that occurs due to the presence of electric charge. Electricity helps in understanding the concept of electricity on the basic level. The nucleus of an atom is called a nucleus which consists of positively charged particles called protons and uncharged particles called neutrons. When an outside force creates imbalance in the protons and electrons, an atom may lose or gain an electron. Electric current is created due to free movement of the electrons. Hence, the flow of the charges leads to production of electricity. 

Electric current and Electric circuit:

  • Electric current is the charge on a fleet of electrons flowing in a circuit. There are two types of electric charge which are positive charge and negative charge. The same charges repel each other and opposite charges attract each other
  • The small area around electric charge where its effect can be felt is known as electric field
  • The electric circuit is the path through which the electric current flows. For the flow of electricity, a close electric circuit is required
  • By convention, the path of current is taken opposite to the path of the float of electrons. It is the physical field that surrounds electrically charged particles and exert force on the charged particles around it
  • SI unit of electrical charge is Coulomb (C)
  • The electric current is expressed by means of a unit referred to as Ampere (A), named after the French scientist, Andre-Marie Ampere (1775–1836)
  • Electric current is measured by means of a tool referred to as Ammeter

Electric potential and potential difference:

  • Potential difference is the difference between two points that represents work involved or energy released in transfer of a unit of electricity from one point to another
  • Electric current is the flow of charged particles like electrons or ions through an electrical conductor
  • The electric potential is also known as the electric field potential and refers to the amount of work energy needed to move a unit of electric charge from one point to another in an electric field
  • The SI unit of electrical potential difference is volt (V), named after Alessandro Volta (1745–1827), an Italian physicist
  • Potential difference is measured through a tool referred to as the Voltmeter that’s continually linked in parallel

Electricity  – Understanding of Ohm’s law:

Ohm’s Law helps in showing the relationship between electric current and potential difference. According to Ohm’s law, the voltage across the conductor is directly proportional to current at constant temperature and physical conditions. It states that the potential difference (V) throughout the ends of a given steel twine in an electric circuit is without delay proportional to the current flowing (I) through it, furnished its temperature stays the identical.

V ∝ I

V/I = constant = R (R is the resistance)

V = IR

Resistance:

  • It is the assets of a conductor to face up to the float of fees through it
  • Its SI unit is ohm and is represented by the symbol Ω
  • Current through a resistor is inversely proportional to its resistance
  • An issue used to alter current without converting the voltage supply is referred to as variable resistance
  • In an electric circuit, a tool referred to as rheostat is frequently used to alternate the resistance within the circuit
  • Factors on which the resistance of a conductor depends: its period, its location of cross-segment and the character of its cloth
  • Resistance of a uniform steel conductor is without delay proportional to its period (l) and inversely proportional to the location of cross-segment (A)
  • Both the resistance and resistivity of a fabric range with temperature

Resistors in Series:

In the resistors in series, there is one path for flow of electrons. The flow of the current is the same throughout as it is a closed circuit and the devices are connected in a continuous row along the circuit loop. A single defect will stop the working of the entire circuit.

  • Current is identical in each part of the circuit or the identical current through every resistor
  • It has a higher output voltage and carries the same current throughout the circuit
  • Disadvantage: When one issue fails, the circuit is damaged and not one of the additives works

Resistors in Parallel:

  • The parallel circuit is an electric circuit with two or more paths for the flow of the current. In this all the components have the same amount of voltage. In a parallel circuit, damage to one component does not stop the flow of current through other components
  • Parallel circuit divides the current through the electric gadgets

 Conclusion  

Electricity is a form of energy, and the flow of electricity is called an electric current. There are two types of electric circuits which are closed and open circuits. However, a closed circuit is important for the continuous flow of electricity. The topics discuss the basics of series and parallel resistors and their advantages.