Seebeck-Effect-Thermoelectricity

 Q. Define thermoelectricity?

Thermoelectricity:

It is the phenomenon in which heat energy is directly converted into electrical energy when two different metals are joined and their junctions are kept at different temperatures.

Q. What is thermocouple?

Thermocouple:

A thermocouple is a device made of two dissimilar metals joined at two junctions (one hot and one cold ) which produces an emf due to the temperature difference.

Q. What is Seebeck effect?

Seebeck Effect:

The Seebeck effect is the production of an emf in a closed circuit made of two different metals when their junctions are maintained at different temperatures.

Or

The Seebeck effect is the phenomenon in which an emf (voltage) is produced when two dissimilar metals form a closed circuit and their junctions are kept at different temperatures.

The size of the emf depends on the metals used and the temperature difference between the two junctions.

For curious minds

The Spark of Heat: The Story of Thermoelectricity

 A long time ago, in the year 1821, there lived a curious scientist named Thomas Seebeck. He loved to play with magnets, wires, and bits of metal. One chilly morning, while warming his hands by the fire, he had a bright idea!

“What happens,” he wondered, “if I join two different metals together and heat one end while keeping the other cool?”

He quickly twisted two wires (one of iron and one of copper) and made tiny loops at both ends. Then he held one end near the fire (the hot junction) and left the other end on his cold table (the cold junction).

To his surprise, something amazing happened : a magnetic needle nearby started to move!

Thomas was shocked . He realized that the heat had created electricity in the wires. The difference in temperature between the two ends made tiny electric charges start to move just like in a battery!

And that’s how thermoelectricity was discovered the idea that heat can make electricity.

Today, this same principle is used in thermocouples to measure temperature and even in space probes to make electricity from the Sun’s heat!

So, thanks to Thomas Seebeck’s curious mind, we now know that even a little bit of heat can make a powerful spark of science!