Relevance: GS III (Science & Tech – Everyday Science) | Source: The Indian Express

1. What is the Context?

War in the Middle East has made cooking gas (LPG) expensive.

To save money, many Indian families are shifting to electric induction stoves.

UPSC loves to ask questions about the simple, everyday science behind such common household items.

2. How Does It Work? (The Magic of Magnets)

A normal gas stove uses actual fire. An induction stove uses magnets. Here is the simple step-by-step science:

The Coil: Hidden inside the stove is a copper wire. When you plug it in, electricity flows through it.

The Invisible Magnet: This electricity creates an invisible magnetic field just above the glass top.

The Magic in the Pan: When you place a metal pan on the stove, this magnetic field enters the metal. It forces the tiny electrons inside the pan to run around in circles. These spinning circles of electricity are called Eddy Currents.

The Heat: As these electrons run around inside the metal, they create “electrical friction.” This friction makes the pan incredibly hot.

The Result: The glass stove itself does not get hot; the magnetic field forces the pan to heat itself up!

3. The “Magnetic” Utensil Rule

Because the stove uses magnetism, it only works with utensils that a magnet can stick to (like iron or special steel).

Utensils made of glass, copper, or pure aluminum will not work on an induction stove.

4. Why is it so efficient?

No Heat Wasted: In a normal gas stove, more than half the heat escapes into the air, making your kitchen hot.

High Efficiency: Because an induction stove creates heat directly inside the metal pan, almost 90% of the energy goes straight into your food.

The Future Link: If millions of homes switch to electric cooking, India will need much more electricity. This makes rooftop solar schemes incredibly important to handle the load.

The “UPSC Trap”

The “Hot Glass” Trap: UPSC will try to trick you by saying, “An induction stove works by heating its glass surface, which then heats the pan.” Incorrect. The glass remains mostly cool. The heat is born directly inside the metal pan.

The “Any Metal” Trap: UPSC might say any metal utensil can be used. Incorrect. It strictly requires magnetic metals (ferromagnetic) like iron or steel.

UPSC Value Box

Key Word / Scheme	Simple Meaning
Eddy Currents	Invisible circles of electricity created inside a metal pan by a magnetic field. This is what actually generates the heat to cook your food.
PM Surya Ghar Yojana	A government scheme helping families put solar panels on their roofs, which can provide free electricity to run these induction stoves.

Q. With reference to the working principle of an induction cooktop, consider the following statements:

It cooks food by transferring heat directly from a red-hot heating element located just below the glass surface.
The heating process relies on the creation of ‘eddy currents’ inside the base of the cooking vessel.
Any metallic vessel, including pure aluminum and copper pans, can be effectively used for cooking on an induction stove.

Which of the statements given above is/are correct?

(a) 1 and 2 only
(b) 2 only
(c) 2 and 3 only
(d) 1, 2 and 3

Correct Answer: (b)