10th CBSE Electricity important notes

                                   

 10th  CBSE Electricity important notes and formulas

ALL DEFINITIONS: 

Current:- the amount of charge flowing through a particular area in unit time

One ampere:- One ampere is constituted by the flow of one coulomb of charge per second.

Potential difference:-  The electric potential difference between two points in an electric circuit carrying some current is the work done to move a unit charge from one point to the other.

One volt:- One volt is the potential difference between two points in a current carrying conductor

when 1 joule of work is done to move a charge of 1 coulomb from one point to the other.

Ohm’s law:- The potential difference, V, across the ends of a given metallic wire in an electric circuit is directly proportional to the current flowing through it, provided its temperature remains the same. This is called Ohm’s law.

One Ohm:- If the potential difference across the two ends of a conductor is 1 V and the current through it is 1 A, then the resistance R, of the conductor is 1 Ohm.

Variable resistance:- A component used to regulate current without changing the voltage source is called variable resistance.

Heating effect of electric current:- If the electric circuit is purely resistive, that is, a configuration of resistors only connected to a battery; the source energy continually gets dissipated entirely in the form of heat. This is known as the heating effect of electric current.

Joule’s law of heating:- The law implies that heat produced in a resistor is directly proportional to

(i)  the square of current for a given resistance, 

(ii) resistance for a given current, and 

(iii) the time for which the current flows through the resistor.

Electric power:- The rate at which electric energy is dissipated or consumed in an electric circuit is called electric power.

One Watt:- It is the power consumed by a device that carries 1 A of current when operated at a potential difference of 1 V.

10th  CBSE Electricity

SI UNITS:

Charge(Q)  - Coulomb (C)

Current (I)  - Ampere (A)

Potential difference (V) - Volt (V)

Resistance (R) - Ohm (Ω)

Resistivity (ρ) - Ohm meter (Ωm)

Heat (H) - Joule (J)

Power (P) - Watt (W)

Commercial unit of electrical energy - Kilowatt hour (kW h)

1 kW h = 1000 watt × 3600 second

= 3.6 × 10⁶ watt second

= 3.6 × 10⁶ joule (J)