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Light, Sound and Waves

How to make a smoke box

Teaching Guidance for 14-16 PRACTICAL PHYISCS

Obtain or construct a wooden box 30 cm high and wide, and 60 cm in length.

  1. Fit panes of window glass in the top and front of the box. The glass panes can be held in place with silicone sealant.
  2. Leave the back open and cover with loosely hung black cloth that drapes like a curtain. Hang this curtain in two sections, with a 10 cm overlap at the centre of the box. Paint the inside of the box with mat black paint.
  3. Cut a window 10 cm high and 5 cm wide midway between the top and bottom of one end, and 8 cm or 10 cm from the glass front. This window lets in light rays.
  4. You can cover the window with different kinds of openings cut from cardboard and fastened with drawing pins.
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