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How does an object's shape relate to its size? What does
physics have to say about the problems objects encounter
as they are scaled larger or smaller?

THE PHYSICS OF SCALING

There is a great deal of geometry involved...

A. First you see a surface of a cube. It
takes 6 of these surfaces to create the
closed cube. What is the area of one
side of the cube? (Place the mouse over
the numbers to see the answer.)

B. What is the total surface area of the
cube? Remember that there are 6 sides.
(Place the mouse over the numbers to see the
answer,)

C. What is the volume of the cube?
(Place the mouse over the numbers to see
the answer.)

D. What is the new surface area when
each side is doubled (multiplied by 2)?
(Place the mouse over the numbers to see the
answer.)

E. What is the new volume when
each side is doubled? (Place the
mouse over the numbers to see the answer.)

F. When the each side doubles then
the surface area is multiplied by __?
(Place the mouse over the numbers to see the
answer.)

G. When the side doubles then the
volume is multiplied by what number?
(Place the mouse over the numbers to see the
answer.)

AS YOU SEE, THE VOLUME INCREASES MUCH MORE THAN THE SURFACE
AREA AS THE OBJECT IS SCALED LARGER!

1. The mass of an object and therefore its weight.

2. The heat produced by the body--it's all in your "guts"!

1. The way your body cools off--your skin's surface area.

2. The air resistance or drag as an object moves through the air
or water. That's why a parachute slows down when open
but falls rapidly when packed up.

3. Surface tension with water is based on the surface area
touching the water. A razor blade will float lying flat on the
water but sink when the sharp edge is dropped in first.

4. The strength of the bones or skeleton depends on the cross
section area of the bones.

GIANT INSECTS?

MICE AND ELEPHANTS

SIZE & SHAPE