During World War II, radios were one of the fastest ways to talk to people. These devices were used in military headquarters and on battlefields to send secret information. They were also used by people at home to listen to music and news reports.
Radios use radio waves to send information. We can’t see radio waves, but they move like waves in the ocean. They can carry music, conversations, and even pictures through the air. Today, many devices use radio waves, including cell phones and Wi-Fi. Let’s try an easy experiment to understand how radio waves work.
What You'll Need:
- Turn on the AM radio and tune it until you hear static.
- Hold the battery near the radio antenna.
- Quickly tap the two terminals of the battery with your coin.
- As you tap the coin, you should hear a crackle from the radio. This crackle means the coin is transmitting radio waves.
You have just created a simple radio transmitter!