David J. Littleboy <davidjl@[EMAIL PROTECTED]
> wrote:
>
> Overheard (really!) in a Navy ROTC course* at a well-know institute of
> higher education in the US.
>
> Professor: We will now compute the density of sea water in slugs per
cubic
> yard.
> Cadet: Sir! Excuse me, sir! But, sir! Are you serious or making a joke,
sir?
> Professor: I'm terribly sorry, but I'm serious.
>
> *: Air, Water, and Interface Vehicles. A seriously great course for
anyone
> even vaguely interested in boats.
If he allows for a slight approximation then this is actually
a pretty good question for remembering useful facts.
- density of seawater is 64 pounds per cubic foot
- acceleration due to gravity is a little over 32 feet/second^2
- Therefore very nearly 2 slugs per cubic foot of seawater
- 27 cubic feet in a cubic yard
- Therefore nearly 54 slugs per cubic yard of seawater
Now if he insisted on a more exact answer of 53.7something,
the simplicity of the question would be lost, but if "nearly 54"
is a good enough answer then it is good practice for quick mental
calculations and remembering acceleration due to gravity and
the density of seawater.
Peter.
--
pirwin@[EMAIL PROTECTED]
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