PURPOSE: To demonstrate focusing of heat waves by a concave mirror.
DESCRIPTION: The arc lamp with condenser lens produces a nearly parallel beam of heat. The parabolic concave mirror focuses the heat onto the match head, lighting the match in about ten seconds from a distance of about ten feet.
REFERENCES: (PIRA 4B40.10)
EQUIPMENT: Arc lamp with condenser lens, parabolic concave mirror and match holder on optical rail on rolling table.
SETUP TIME: 5 min.
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