In article
<3c4b21f1-bf10-4b61-b3f2-f6875703d3b4@[EMAIL PROTECTED]
>,
google@[EMAIL PROTECTED]
says...
> On 6 Apr., 21:17, RKL <mary...@[EMAIL PROTECTED]
> wrote:
> > Here's an interesting one:
> >
> > A lifeguard stationed on a beach with a straight shoreline sees a
> > swimmer in trouble 150 meters down the beach and 60 meters out in the
> > water.
> >
> > The lifeguard can run 8 m/s on the beach and swim 2 m/s in the water.
> >
> > What path down the shoreline and out into the water should the
> > lifeguard take to reach the swimmer in the SHORTEST AMOUNT OF TIME?
> >
> > --
> > He who waits to do a great deal of good at once, will never do
anything.
>
> Use what you learned in optics :)
>
Precisely. As everyone knows, the speed of light over sand is exactly four
times the speed of light over water, so the
lifeguars should always run/swim directly towards the point at which he
can 'see' the swimmer.
Mike
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