I'll have to actually try this approach with the students tomorrow at
tomorrow's review session. The feedback here has helped refine and
sharpen the analogy.
Certainly, the brain doesn't have a specific memory limit like an iPod,
but the rate at which info can be "uploaded" IS certainly limited (by
time, motivation, distractions, ability...). This means that it is
important to "upload" the most valuable info.
Also, I doubt the students really understand the details of compression,
but I don't think that matters. They do know that a CD will hold ~20
uncompressed songs but hundreds of compressed songs. The analogy that
raw information is a poor format for their brain should hopefully sink
in.
One option to drive this home might be to list a lot of equations that
they might need. On one sheet, just list the equations in one form, on
the other list various permutations (V=IR R=V/I I=V/R V/IR=1). The
first is "uncompressed"; the second is "compressed" and should LOOK a
lot less intimidating. Or make several tables for distance as a
function of time, initial speed, and acceleration on one sheet, and "x =
x0 + v0t + 1/2 at^2" on the other.