# PSEB 10th Class Science Notes Chapter 12 Electricity

This PSEB 10th Class Science Notes Chapter 12 Electricity will help you in revision during exams.

## PSEB 10th Class Science Notes Chapter 12 Electricity

→ Electric current is the rate of flow of charge Q through the conductor or it is the charge Q flowing per unit time i.e., I = $$\frac{Q}{t}$$

→ Charge always flows from a body at a higher potential to a body at a lower potential.

→ Electrostatic potential determines the direction of flow of charge from one body to the other when they are brought in contact. → Electrostatic potential at a point is defined as the amount of work done is bringing a unit positive test charge from infinity to that point.

→ Conductors have a large number of free electrons whereas insulators have very few free electrons. The motion of free electrons constitutes the electric current.

→ An electric circuit is a closed path through which electrons flow readily.

→ As per convention, the direction of current is taken as opposite to the direction of the flow of electrons.

→ Electric Current: The rate of flow of charge through a conductor is called electric current.
I = $$\frac{Q}{t}$$

→ Ohm: The resistance of a conductor is said to be 1 ohm if a potential difference of 1 volt is maintained between its ends and it allows 1 ampere of current to flow through it.

→ Voltmeter: It is a device used to measure the potential differences.

→ Conductor: Those substances which allow the current to flow through them are called conductors or good conductors.

→ Insulators: Those substances which do not allow the current to flow through them are called insulators.

→ Ammeter: It is an instrument used to measure electric current.

→ Rheostat: It is a device that is used to increase or decrease the current flowing through the electric circuit. → One Volt: If 1 coulomb of charge is allowed to pass through a conductor and in doing so 1 joule of work is done then the potential difference across its ends is 1 volt.

→ Ohm’s Law: The ratio of potential difference across the ends of a conductor and the current flowing through it is always constant, provided the physical state of the conductor such as temperature and pressure remains unchanged.
i.e. V ∝ I or $$\frac{V}{I}$$ = R

→ Electrical Energy: The capacity of doing work by an electric current is called electrical energy.

→ Electric Power: The rate of consumption of electric energy in a conductor is called electric power.

→ Watt: Watt is an S.I. unit of electric energy in which 1 joule of work is done in 1 sec. Kilowatt. It is the power of an agent which can do 1000 joule of work in 1 second.

→ Kilowatt Hour: It is that electric energy which is consumed in an electric circuit in 1 hour. → Coulombs’ Law: Electric force between two charged particles is directly proportional to the product of the two charges and inversely proportional to the square of the distance between them.
F = K$$\frac{q_{1} q_{2}}{r^{2}}$$

→ Joule’s Law of Heating Effect. If T is the electric current that flows through a resistor ‘R’ and as a result of which heat produced is ‘H’. Then heat produced is directly proportional to the square of the current and time ‘t’
H = I2 Rt