I guess I’m showing my age when I say I can remember my family’s first remote control TV. It was amazing. My dad could change from his favorite news channel to whatever channel the game was on without anyone having to walk to the TV and turn the dial. My career as the official changer was over.
Soon after that, I remember my brother getting a remote control car. The car raced around the kitchen linoleum floor while he sat in a chair with the controller steering it from a couple of feet away. Magic!
After that came the cordless phone that totally changed our world. Walking around the house while talking on the telephone? No cord to get tangled? These were exciting times.
What makes all of those technological advancements possible was the discovery of the ability to transfer information through the air without wires or any other connection. This information travels from the remote control to the car, TV, telephone or any other remotely controlled devices by invisible radio waves.
Each device can receive information from a certain frequency of radio waves. That is why the controller of one your remote control cars won’t work on the other. These radio waves are sent out into the air by a transmitting antenna and received by a receiving antenna. The waves of information can travel through the air easily because air is a good transmitter. Not all materials are.
Experimenting With Good And Bad Transmitters
- Remote control car
- Aluminum foil
- Plastic wrap
Cover the remote (or antenna, if external) with one of the materials (paper, aluminum foil, etc.). Try to use the remote to control the car. Does it still work? Try all of your materials. Make a note of how the remote works when covered with each material. Try other materials you find around the house and note how the remote works when covered with each.
Try all of your materials. Make a note of how the remote works when covered with each material. Try other materials you find around the house and note how the remote works when covered with each.
Some materials are excellent transmitters of radio waves and allow them to pass right through. Other materials are poor transmitters and block the radio waves.
Which materials did you find to be good transmitters and which are poor?