Question 515272
{{{ I = k*(1/d^2) }}}
Find {{{k}}} using the given data:
{{{ I = 160 }}}
{{{ d = 4 }}}
{{{ 160 = k*( 1/16) }}}
{{{ k = 2560 }}}
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If {{{ I = 90 }}}
{{{ 90 = 2560*(1/d^2) }}}
{{{ d^2 = 2560/90 }}}
{{{ d^2 = 256/9 }}}
{{{ d = 16/3 }}} m
When {{{ I = 160 }}}, {{{d = 4 }}},
or {{{ 12/3 }}}
The point where {{{ I = 90 }}} is
{{{ 16/3 - 12/3 = 4/3 }}} m further