The question is why is an LC circuit often called a tank circuit.
One possible answer is contained in a paragraph in Wikipedia regarding
LC circuits, which is as follows:
"History
The first evidence that a capacitor and inductor could produce
electrical oscillations was discovered in 1826 by French scientist Felix
Savary <http://en.wikipedia.org/wiki/Felix_Savary>.^[2]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Blanchard-2> ^[3]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-3> He found that when
a Leyden jar <http://en.wikipedia.org/wiki/Leyden_jar> was discharged
through a wire wound around an iron needle, sometimes the needle was
left magnetized in one direction and sometimes in the opposite
direction. He correctly deduced that this was caused by a damped
oscillating discharge current in the wire, which reversed the
magnetization of the needle back and forth until it was too small to
have an effect, leaving the needle magnetized in a random direction.
American physicist Joseph Henry
<http://en.wikipedia.org/wiki/Joseph_Henry> repeated Savary's experiment
in 1842 and came to the same conclusion, apparently independently.^[4]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Kimball-4> ^[5]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Huurdeman-5> British
scientist William Thomson <http://en.wikipedia.org/wiki/William_Thomson>
(Lord Kelvin) in 1853 showed mathematically that the discharge of a
Leyden jar through an inductance should be oscillatory, and derived its
resonant frequency.^[2]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Blanchard-2> ^[4]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Kimball-4> ^[5]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Huurdeman-5> British
radio researcher Oliver Lodge
<http://en.wikipedia.org/wiki/Oliver_Lodge>, by discharging a large
battery of Leyden jars through a long wire, created a tuned circuit with
its resonant frequency in the audio range, which produced a musical tone
from the spark when it was discharged.^[4]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Kimball-4> In 1857,
German physicist Berend Wilhelm Feddersen
<http://en.wikipedia.org/wiki/Berend_Wilhelm_Feddersen> photographed the
spark produced by a resonant Leyden jar circuit in a rotating mirror,
providing visible evidence of the oscillations.^[2]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Blanchard-2> ^[4]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Kimball-4> ^[5]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Huurdeman-5> In 1868,
Scottish physicist James Clerk Maxwell
<http://en.wikipedia.org/wiki/James_Clerk_Maxwell> calculated the effect
of applying an alternating current to a circuit with inductance and
capacitance, showing that the response is maximum at the resonant
frequency.^[2]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Blanchard-2> The
first example of an electrical resonance
<http://en.wikipedia.org/wiki/Resonance> curve was published in 1887 by
German physicist Heinrich Hertz
<http://en.wikipedia.org/wiki/Heinrich_Hertz> in his pioneering paper on
the discovery of radio waves, showing the length of spark obtainable
from his spark-gap LC resonator detectors as a function of
frequency.^[2]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Blanchard-2>
One of the first demonstrations of resonance
<http://en.wikipedia.org/wiki/Resonance> between tuned circuits was
Lodge's "syntonic jars" experiment around 1889.^[2]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Blanchard-2> ^[4]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Kimball-4> He placed
two resonant circuits next to each other, each consisting of a Leyden
jar connected to an adjustable one-turn coil with a spark gap. When a
high voltage from an induction coil was applied to one tuned circuit,
creating sparks and thus oscillating currents, sparks were excited in
the other tuned circuit only when the circuits were adjusted to
resonance. Lodge and some English scientists preferred the term
"/syntony/" for this effect, but the term "/resonance/" eventually
stuck.^[2]
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Blanchard-2> The
first practical use for LC circuits was in the 1890s in spark-gap radio
transmitters <http://en.wikipedia.org/wiki/Spark-gap_transmitter> to
allow the receiver and transmitter to be tuned to the same frequency.
The first patent for a radio system that allowed tuning was filed by
Lodge in 1897, although the first practical systems were invented in
1900 by Italian radio pioneer Guglielmo Marconi
<http://en.wikipedia.org/wiki/Guglielmo_Marconi>.^[2]"
<http://en.wikipedia.org/wiki/LC_circuit#cite_note-Blanchard-2>
^So, the first LC circuits were actually contained within Leyden jars.
Perhaps they were called tanks.
^Or maybe not.
^73, Colin K7FM
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