4B40.10 - Light the Match

Code Number:
4B40.10
Demo Title:
Light the Match
Condition:
Good
Principle:
Radiation, Reflection, and Focusing of Heat
Area of Study:
Heat & Fluids
Equipment:
Parabolic mirror with match holder assembly, Parabolic mirror with heater coil assembly, and Variac.
Procedure:

Place the parabolic mirrors on rods at each end of the table. Use the rod attached to mirror with the match holder and adjust both mirrors to the same height. Make sure they are as parallel to each other as you can eyeball it, (doesn't need to be measurement accurate). Turn the Variac all the way up and wait 45 seconds. At about 30 seconds the match will start to visibly smoke and will burst into flames at about 45 seconds.

If precise alignment is necessary, you may use a radiometer as the detector to find and fine tune the focal point.

References:
  • Richard E. Berg, "Heat-Wave Focusing by Concave Reflectors", TPT, Vol. 28, # 1, Jan. 1990, p. 56.
  • Thomas B. Greenslade, Jr., "19th Century Textbook Illustrations XXX - Demonstrations of Thermal Radiation", TPT, Vol. 17, # 5, May 1979, p. 320.
  • James Evans and Brian Popp, "Pictet's Experiment: The Apparent Radiation and Reflection of Cold", AJP, Vol. 53, #8, Aug. 1985, p. 737.
  • Julien Clinton Sprott, Physics Demonstrations,  "2.14",  p. 101, ISBN 0-299-21580-6.
  • J. Klinger Scientific Apparatus, "Infrared Radiation", Experiments in Optics, Part 1, #14.
  • W. Bolton, "The Efficiency of Reflectors on Electric Fires", Book 2 - Waves and Particles, Physics Experiments and Projects, 1968, p. 86.
  • Joseph Frick, "# 372 & 373 - For Remaining Experiments in Radiant Heat", Physical Technics: Or Practical Instructions for Making Experiments in Physics and the Construction of Physical Apparatus with the Most Limmited Means, p. 447.
  • "Reflectors, etc., For Radiation of Heat", Pike's Illustrated Catalogue of Scientific & Medical Instruments, Pike's Illustrated Descriptive Catalogue of Optical, Mathematical, and Philosophical Instruments, 1984, p. 98.

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