|Why is the interior of the Earth hot?
|Question Date: 2005-01-10|
There are two reasons. First, when the earth
formed 4500 million years ago, it was molten
throughout...a giant magma ocean!!!. It has been
cooling ever since by losing heat through the
surface. The second reason why its still hot is
that certain radioactive elements like uranium and
potassium spontaneously decay to other elements
(lead and argon) in radioactive decay. When the
parent element decays to the daughter element,
HEAT is generated.
The interior of Earth is hot because of a process
called radioactive decay.Certain elements found in
Earth are unstable.Through time, an atom of these
elements will "kick out" or "lose" protons or
neutrons. (Remember that atoms are made up of
protons, neutrons, and electrons.) This change
produces energy in the form of heat. Uranium is
one element that undergoes radioactive decay to
produce heat in the Earth.
The interior of the Earth is hot for several
reasons and much of the heat is left over from the
formation of the earth 4.6 billion years ago. The
Earth formed out of a spinning mass of gases and
meteorites that were drawn together by the force
of gravity. As they collided together into the
earth,they produced a tremendous amount of heat.
The earth has cooled quite a bit,but it is still
as much as 4300C (7770F) in the middle. The
material the earth is made of also contains many
radioactive elements. As these elements decay,
they release more energy. So the interior of the
earth is hot because of gravitational energy,
impact energy, and radioactive energy.
All the best
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