Regarding Peter Neilsons story:

> He said to himself, "That sucker's so heavy it's not going
> anywhere," and didn't tie it at all.  At the first corner
> the piano (being top-heavy) jumped out of the truck.

    F = MA  (Force = Mass x Acceleration)

Since the force exerted on an object is proportional to the mass, the
actual mass of the object is irrelevant.  We are deceived by the fact
that it is difficult to move a heavy piano on a flat surface using
muscle power.  But a truck making a turn that exerts a 0.2 g lateral
acceleration (moderate turn) will be like pushing a 600 lb. object
sideways with a force equivalent to 120 lbs.

A more appropriate concern might be the friction between the piano and
the truck bed.  Since that is tough to control, tie it down.  I once
had to make an evasive maneuver in my little '64 Spitfire to avoid
slamming into an airborne refrigerator door that someone neglected to
tie down.

Larry Toto