The electric kettle was invented in 1891 but had design flaws, as the heating element was separate from the water. The modern electric kettle design places the heating element inside the water, improving efficiency. An electric kettle works by passing electricity through a high resistance heating element, generating heat to boil the water. For safety, a bi-metallic strip automatically shuts off the kettle once it reaches boiling point to prevent overheating. Arthur Leslie Large is credited with inventing the improved electric kettle design still used today.

1. EARLY ELECTRIC
KETTLE AND IRON
Joan Vilanova 1r A
Madalin Enoiu 1r A

2. INDEX
• The history of electric kettles
• Operation
• Bibliography

3. The history of electric kettles .
• By the 19th century, kettle makers switched from iron to copper because it
conducted heat more efficiently.
• The next significant improvement – the so-called "whistling kettle" – came
along in the early 20th century and represented a major step in the evolution
of the kettle.
• The first kettle to use electricity to heat water came from Carpenter Electric
Company in Chicago in 1891. However, the water took more than 10
minutes to come to a boil because of a major design problem – the heating
element was in a separate compartment, rather than in the water as is the
case in modern kettles.
• Arthur Leslie Large is credited with inventing the electric kettle .

4. Operation
• Here's how an electric kettle works: Electricity moves through an
element of high resistance, which generates heat that it transfers to
the water.
• At the moment the temperature of the liquid reaches 100 degrees
Celsius, its boiling point, the resulting steam warms a strip
composed of two dissimilar kinds of metal, which curves due to the
fact one of the metals expands more rapidly.
• The heating connection is then broken, preventing electricity from
reaching the element, effectively shutting off the kettle.
• Such a safety feature prevents the scalding water from becoming a
hazard if the person tending it becomes distracted and neglects the
steaming appliance. The "cut-out" device represents a significant
advantage over whistling kettles, which keep boiling, and whistling,
until someone turns down the heat.

5. Bibliography
MAGNET LAB
eHow
Vikipèdia

6. Bibliography
MAGNET LAB
eHow
Vikipèdia