Name: Ohm’s Law & Introduction to Electric Resistance
Uploaded: 2019-07-19
Duration: 8 min 43 s
Description: In our attempt to establish a relationship between current and voltage, we will discover a new physical quantity in this video. Let's watch and learn.

Question

What is Joule&rsquo;s heating effect? How can it be explained experimentally? List its few applications in daily life.

Accepted Answer

Joule's Law of Heating: If the electrical circuit is purely resistive, that is a configuration of resistors only connected to battery, the source energy continually gets dissipated in the form of heat. This is known as Joule’s heating effect of electric current.
Joule’s law of heating states that the heat produced in resistor is

directly proportional to square of current passing through it i.e. $H \propto I^{2}$

directly proportional to resistance i.e. $H \propto R$

directly proportional to time during which current flows; i.e. $H \propto t$ .

In a conductor when an electric field is applied across its ends, the free electrons available in it start drifting opposite to the direction of the electric field. These electrons collide with the atoms which have lost the electrons. As a result of these collisions some energy of the electrons is transferred to the atoms which vibrate violently as they gain energy. Thus, heat is developed in the conductor. Greater the current, greater will be the rate of collision and so greater will be the heat produced.

The four applications in daily life are:
1. In electrical heaters
2. In electrical iron
3. In electrical fuse wire
4. In electrical bulb

What is Joule’s heating effect? How can it be explained experimentally? List its few applications in daily life.

Important Questions on Electricity

Learn and Prepare for any exam you want !