Engaging questions:

  • When a TV channel is changed, certain information is sent from the remote control to the television set. How does the remote control communicate with the TV set?
  • How does the human eye work?
  • Does every person perceive colours in the same way?
  • Why are the dog whistles inaudible to people? more useful for sound unit

Equipment: TV remote control (VCR or DVD player), cell phone with a camera (or digital camera, camcorder).

Description of the Activity :

Students try to see the light from the remote control with the naked eye and through the camera. They may take photos or make a video


  • Why cannot we see the light emitted by the TV remote control?
  • Why does not every remote control works with each TV set?
  • Are we able to switch the TV channel turning the remote control in the opposite direction than our TV set?
  • Daltonism is a disorder of colours vision and recognition. With what may it be related? Compared to the camera, are we all daltonists?
  • How does a thermal imaging camera work?
  • Why do cats see well at night?