14-05-2025
Ask Fuzzy: How does an induction cooker work?
You can usually tell whether a device is inefficient by the amount of wasted heat.
An obvious example is the internal combustion engine which burns more than half its fuel doing nothing more than getting hot.
The best that most cars can manage is about 20-40 per cent efficiency. That means 60-80 per cent is wasted. Great if you want to cook sausages, but it doesn't you get anywhere.
Televisions, computers and power charges all get warm to varying degrees and, in each case, that means wasted energy.
Then there are kitchen stoves such as gas and those with old-style heater elements. They certainly get hot but, as with cars, much of that goes into heating itself and the air around it without doing any useful work.
A good indicator that induction cooktops are highly efficient (about 84 per cent) is that the "hot plates" are often cool enough to touch (carefully) shortly after they finish cooking.
The history of electromagnetic induction goes back to 1820 when Danish physicist Hans Christian Oersted discovered that an electric current generates a magnetic field.
Then in 1821 English physicist Michael Faraday made a primitive electric motor by placing a magnet near a piece of wire. When he fed an electric current into the wire, it generated a magnetic field, pushing itself away from the permanent magnet.
In 1831, he flipped the idea around by rotating a coil of wire through a magnetic field to induce an electric current, thus inventing the electricity generator.
MORE ASK FUZZY:
Now we see induction used in electric toothbrushes cradles and wireless phone chargers.
As the name implies, induction stoves work on the same principle.
An alternating current running through the tightly wound metal coil inside a cooking zone induces a high-frequency alternating magnetic field.
That produces whirling electrical currents inside the pan. The repeated magnetising and demagnetising (magnetic hysteresis) turns it into a heater.
The beauty of this is that it heats the pan directly instead of an element and the air around it. If there's no pan on the cooking zone, the cooking zone stays cold.
Although your home power supply alternates at 50Hz, an induction cooktop is 20-40kHz, which is 500 to 1000 times faster.
That offers a couple of advantages. One is that being above the range of hearing, stops any annoying buzzing.
The other is that it prevents your pots from dancing around on the cooktop.
The Fuzzy Logic Science Show is at 11am Sundays on 2xx 98.3FM.
Send your questions to AskFuzzy@ Podcast:
You can usually tell whether a device is inefficient by the amount of wasted heat.
An obvious example is the internal combustion engine which burns more than half its fuel doing nothing more than getting hot.
The best that most cars can manage is about 20-40 per cent efficiency. That means 60-80 per cent is wasted. Great if you want to cook sausages, but it doesn't you get anywhere.
Televisions, computers and power charges all get warm to varying degrees and, in each case, that means wasted energy.
Then there are kitchen stoves such as gas and those with old-style heater elements. They certainly get hot but, as with cars, much of that goes into heating itself and the air around it without doing any useful work.
A good indicator that induction cooktops are highly efficient (about 84 per cent) is that the "hot plates" are often cool enough to touch (carefully) shortly after they finish cooking.
The history of electromagnetic induction goes back to 1820 when Danish physicist Hans Christian Oersted discovered that an electric current generates a magnetic field.
Then in 1821 English physicist Michael Faraday made a primitive electric motor by placing a magnet near a piece of wire. When he fed an electric current into the wire, it generated a magnetic field, pushing itself away from the permanent magnet.
In 1831, he flipped the idea around by rotating a coil of wire through a magnetic field to induce an electric current, thus inventing the electricity generator.
MORE ASK FUZZY:
Now we see induction used in electric toothbrushes cradles and wireless phone chargers.
As the name implies, induction stoves work on the same principle.
An alternating current running through the tightly wound metal coil inside a cooking zone induces a high-frequency alternating magnetic field.
That produces whirling electrical currents inside the pan. The repeated magnetising and demagnetising (magnetic hysteresis) turns it into a heater.
The beauty of this is that it heats the pan directly instead of an element and the air around it. If there's no pan on the cooking zone, the cooking zone stays cold.
Although your home power supply alternates at 50Hz, an induction cooktop is 20-40kHz, which is 500 to 1000 times faster.
That offers a couple of advantages. One is that being above the range of hearing, stops any annoying buzzing.
The other is that it prevents your pots from dancing around on the cooktop.
The Fuzzy Logic Science Show is at 11am Sundays on 2xx 98.3FM.
Send your questions to AskFuzzy@ Podcast:
You can usually tell whether a device is inefficient by the amount of wasted heat.
An obvious example is the internal combustion engine which burns more than half its fuel doing nothing more than getting hot.
The best that most cars can manage is about 20-40 per cent efficiency. That means 60-80 per cent is wasted. Great if you want to cook sausages, but it doesn't you get anywhere.
Televisions, computers and power charges all get warm to varying degrees and, in each case, that means wasted energy.
Then there are kitchen stoves such as gas and those with old-style heater elements. They certainly get hot but, as with cars, much of that goes into heating itself and the air around it without doing any useful work.
A good indicator that induction cooktops are highly efficient (about 84 per cent) is that the "hot plates" are often cool enough to touch (carefully) shortly after they finish cooking.
The history of electromagnetic induction goes back to 1820 when Danish physicist Hans Christian Oersted discovered that an electric current generates a magnetic field.
Then in 1821 English physicist Michael Faraday made a primitive electric motor by placing a magnet near a piece of wire. When he fed an electric current into the wire, it generated a magnetic field, pushing itself away from the permanent magnet.
In 1831, he flipped the idea around by rotating a coil of wire through a magnetic field to induce an electric current, thus inventing the electricity generator.
MORE ASK FUZZY:
Now we see induction used in electric toothbrushes cradles and wireless phone chargers.
As the name implies, induction stoves work on the same principle.
An alternating current running through the tightly wound metal coil inside a cooking zone induces a high-frequency alternating magnetic field.
That produces whirling electrical currents inside the pan. The repeated magnetising and demagnetising (magnetic hysteresis) turns it into a heater.
The beauty of this is that it heats the pan directly instead of an element and the air around it. If there's no pan on the cooking zone, the cooking zone stays cold.
Although your home power supply alternates at 50Hz, an induction cooktop is 20-40kHz, which is 500 to 1000 times faster.
That offers a couple of advantages. One is that being above the range of hearing, stops any annoying buzzing.
The other is that it prevents your pots from dancing around on the cooktop.
The Fuzzy Logic Science Show is at 11am Sundays on 2xx 98.3FM.
Send your questions to AskFuzzy@ Podcast:
You can usually tell whether a device is inefficient by the amount of wasted heat.
An obvious example is the internal combustion engine which burns more than half its fuel doing nothing more than getting hot.
The best that most cars can manage is about 20-40 per cent efficiency. That means 60-80 per cent is wasted. Great if you want to cook sausages, but it doesn't you get anywhere.
Televisions, computers and power charges all get warm to varying degrees and, in each case, that means wasted energy.
Then there are kitchen stoves such as gas and those with old-style heater elements. They certainly get hot but, as with cars, much of that goes into heating itself and the air around it without doing any useful work.
A good indicator that induction cooktops are highly efficient (about 84 per cent) is that the "hot plates" are often cool enough to touch (carefully) shortly after they finish cooking.
The history of electromagnetic induction goes back to 1820 when Danish physicist Hans Christian Oersted discovered that an electric current generates a magnetic field.
Then in 1821 English physicist Michael Faraday made a primitive electric motor by placing a magnet near a piece of wire. When he fed an electric current into the wire, it generated a magnetic field, pushing itself away from the permanent magnet.
In 1831, he flipped the idea around by rotating a coil of wire through a magnetic field to induce an electric current, thus inventing the electricity generator.
MORE ASK FUZZY:
Now we see induction used in electric toothbrushes cradles and wireless phone chargers.
As the name implies, induction stoves work on the same principle.
An alternating current running through the tightly wound metal coil inside a cooking zone induces a high-frequency alternating magnetic field.
That produces whirling electrical currents inside the pan. The repeated magnetising and demagnetising (magnetic hysteresis) turns it into a heater.
The beauty of this is that it heats the pan directly instead of an element and the air around it. If there's no pan on the cooking zone, the cooking zone stays cold.
Although your home power supply alternates at 50Hz, an induction cooktop is 20-40kHz, which is 500 to 1000 times faster.
That offers a couple of advantages. One is that being above the range of hearing, stops any annoying buzzing.
The other is that it prevents your pots from dancing around on the cooktop.
The Fuzzy Logic Science Show is at 11am Sundays on 2xx 98.3FM.
Send your questions to AskFuzzy@ Podcast:
