Good Day beedee-ga,
Thank you for your question. Here is some information which should
answer your question.
"How does a kettle work?
What happens when a kettle boils?"
"An electric kettle works by transferring heat from an electrical
element to water. Electricity flows into the heating element of the
kettle, that’s the large bit of coiled wire in the bottom. The
electricity is actually insulated from the water - it flows in the
wires inside the element, not through the element itself. If it did
you would risk an electric shock. Inside the element is a resistor,
this heats up when electricity flows through it. All the resistor is
made of is a very very long coil of wire. The atoms that make up the
wire block the electrons from moving, they bump into the atoms and
this bumping around generates heat. The more wire you have squashed
together the more heat that is generated.
Thus the heat is transferred into the water. When a kettle boils the
water molecules have gained enough energy to break away from each
other - they turn into steam. This happens throughout the liquid - so
you get bubbles. The kettle knows when to switch off because there is
a simple thermostat that acts as a safety device turning the kettle
off when it reaches a certain temperature."
Source: ScienceNet - Technology & Engineering
URL: http://www.sciencenet.org.uk/database/Technology/0210/t00373d.html
As you can imagine, a range kettle works in a very similar fashion.
Rather than having a coiled element on the inside of the kettle, the
water boils from the heat transferred through the kettle from the
element underneath the kettle.
Also, you might have seen around a simple coil with a plug. These used
to be quite common in certain parts of the world. All you would do is
put the coil into a container of water, and plug the coil into a power
source (the coil is attached to a wire with a plug). Seeing how simple
the device is, you might get an idea of what a kettle is. The kettle
itself is just a fancy box around the coil that plugs into an
electrical outlet.
Other information which you might find useful is listed below.
"Why does a kettle go quiet just before it boils?"
"As water is heated, dissolved gasses in the water start to come out
of solution. As water approaches boiling point, all the dissolved
gases have been released so there is no more bubbling. This is when
the kettle goes quite. As the water then begins to boil, the
convection currents in the water become very violent and the water
becomes noisy again."
Source: ScienceNet - Physics & Astronomy
URL: http://www.sciencenet.org.uk/database/Physics/Original/p00074d.html
When "electric kettle is turned on, there is a sizzling noise which
then dies away. Why?"
"When a kettle is turned on, the water around the element becomes very
hot immediately while the rest is still cool. Bubbles form and rise
from the element, but when they hit the cold water they collapse. The
noise of this sudden implosion causes the hiss. This noise then dies
away as the rest of the water approaches the same temperature."
Source: ScienceNet - Questions and Answers
URL: http://www.sciencenet.org.uk/database/Physics/Original/p00233d.html
Here is a link to information on electricity, what it is, and how it
works:
Title: What is Electricity?
URL: http://www.powerworks.com.au/pw056whatiselectricity.htm
I hope this answers your question. Should you for any reason be
unsatisfied with my answer, please ask for a clarification, and I will
be sure to provide you with additional information.
Search strategy: Google search for "electric kettle"+"how does"
Regards,
slawek-ga |
