This apparatus demonstrates the independence of horizontal
and vertical velocities. It comprises a polished wooden block 200 mm long, which is pivoted an L-section metal
launching bar
180 mm long. The bar is spring loaded and provided with a trigger catch. A small hole near each end of
the bar serves to
locate a 18 mm diameter steel ball. As and when the catch is released one ball drops vertically
while the other is projected
horizontally. The fact that the vertical velocities of both balls are the same at any
instant, despite the fact that one has
a large horizontal component, is shown by the fact that both hit the floor at
the same instant.
The apparatus is
supplied complete with a pair of steel balls of 18 mm diameter which is
stored in a covered recess in the wooden body.
