Question 697328
They are basically saying that the dragonfly's wing will beat
faster the shorter it is made.
Let {{{ s }}} = speed of the wing in beats / min
Let {{{ w }}} = the length of the wing in inches
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They are say ing that {{{ s = k*(1/w) }}} where {{{ k }}}
is the constant of inverse variation.
given:
{{{ 200 = k*(1/.36) }}}
{{{ k = .36*200 }}}
{{{ k = 72 }}}
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It sounds like the speed of the beating has to be the given
minimum, or the dragonfly  cannot fly.
given:
{{{ s = k*(1/w) }}}
{{{ s = 72*(1/1.2) }}}
{{{ s = 60 }}} beats/sec
{{{ 50 }}} beats/sec is slower that this, so the dragonfly
will not stay aloft beating at this speed