Vibrating Speaker Illusion

This picture was taken when small plastic beads were bouncing on a speaker through which loud music was being played. The speaker was laid flat on its back and the beads were placed on it. Music with a high wave frequency was played meaning that the air fluctuation was fast. This caused the suspension, the flexible rim, to physically vibrate quickly. The beads that were placed on the speaker then bounced up and down. This is because the energy from the sound waves (sound energy) transferred to the beads in the form of kinetic energy and caused them to move rapidly. The concave reflective surface of the cone also provides for a fascinating illusion. It gives the illusion that the picture can be viewed upside down. However, to understand the correct way to look at it, the orange bead must be in the bottom left corner bouncing off the side wall and the blue bead in the bottom centre, both bouncing into the centre of the cone. This illusion is caused by the angle that the picture was taken at, not allowing the viewer to see the wall of the cone that the blue bead is bouncing off of.

Hira Jamal
Emery Collegiate Institute, North York, ON
Second Prize ( 2014 High School Class Project Category )
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