JOULE'S LAW OF HEATING CBSE PHYSICS

 

Statement:
The heat produced in a conductor by an electric current is directly proportional to:

1. The square of the current ($I^2$)

2. The resistance of the conductor ($R$)

3. The time for which the current flows ($t$)

Mathematical form:

H=I2Rt

Where:

• $H$= heat produced (in joules)

• $I$= current (in amperes)

• $R$= resistance (in ohms)

• $t$= time (in seconds)

Explanation:
When an electric current flows through a resistor, the electrical energy is converted into heat due to collisions between moving electrons and atoms of the conductor. This is called the heating effect of electric current.

Applications:

• Electric heaters and geysers

• Electric irons

• Fuses and electric bulbs

• Electric cooking appliances