Clear soft drink bottle has a stoppered hole in the lower half. The bottle contains about 5 ml of a dilute soap solution.
To set up the film, rotate the bottle until all the interior surfaces are wet. Remove the cap and place your palm over the opening. Tilt to bring the solution onto your palm, right the bottle and remove your palm with a rolling motion to pull the film across the opening. Remove the stopper and blow on the flim to move it to the center of the bottle. Seal the bottle and allow the film to drain. The bottle can be passed around the classroom.
Question?
Why does the reflection disapear near the top of the film?
Why are the colors of the reflection subrtractive colors?
