Telephones Alexander Bell Then to Now Be an Inventor Materials Metal Music String Phone Chat Room Sound Waves Tuning Fork Transmit Light Faraday Box Conclusion Quiz Glossary 4 6 8 10 12 14 16 18 20 22 26 28 30 31 32
telephones AN INTRODUCTION Today you can talk to a friend or family member anytime Telephones make it possible The telephone is a machine It lets people talk to each other from far away They can be across the street or across the country A phone changes sound into data The data is sent to another phone It turns the data back into sound
