Brass ball doesn't fit through brass ring until ring is heated.
What it shows:
Most solids (see Comments) expand when heated due to increased atomic and lattice vibrations. In this demo, a brass ring expands when heated to let a previously too small a ball pass cleanly through.
How it works:
The apparatus consists of a brass ring on a handle (figure 1), attached by a chain to a brass ball. Demonstrate that the ball is too large to pass through the ring, then heat the ring over a blue Bunsen flame for about a minute. The...
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