Description: The device consists of a pedestal with a concave
top. Attached to the pedestal is a flat metal leaf spring. A heavy metal ball
and a square card are supplied for demonstration purposes.
Operation: Place the inertia apparatus on a flat, level surface.
Center the square card on top of the pedestal with one edge aligned parallel
to the leaf spring. Place the metal ball on the card directly over the recess
in the pedestal. If the ball rolls off the card, find a more
suitable surface on which to rest the apparatus. If the ball continues to roll off, form a
very slight impression in the card by pressing gently on the ball. It is important to apply only light pressure
to prevent damage to the card.
Pull the spring back gently and release it suddenly so it strikes the edge of the card. It may be necessary to hold the base of the pedestal steady while pulling the spring. The blow from the spring propels the card from beneath the ball. The relatively heavy ball has too much inertia to gain horizontal momentum; consequently it drops into the recess on top of the pedestal.