Question

State Joule's laws of heating regarding electric current.

Hint:

The formula \(H = I^2Rt\) is crucial for solving numerical problems related to heating effects of current.

Answer 1

Step 1: Understanding the Concept:
When an electric current passes through a conductor with some resistance, electrical energy is converted into heat energy.

Step 2: Detailed Explanation:
Joule's laws of heating state that the heat (\(H\)) produced in a conductor is:
1. Directly proportional to the square of the current (\(I\)) flowing through it, when resistance and time are constant (\(H \propto I^2\)).
2. Directly proportional to the resistance (\(R\)) of the conductor, when current and time are constant (\(H \propto R\)).
3. Directly proportional to the time (\(t\)) for which the current flows, when current and resistance are constant (\(H \propto t\)).
Combining these gives the equation \(H = I^2Rt\).

Step 3: Final Answer:
The laws are \(H \propto I^2\), \(H \propto R\), and \(H \propto t\), cumulatively expressed as \(H = I^2Rt\).