Light and Sound

How does sound travel? What is sonar? Why do cats see well in low light? Read this book to find out the answers to these questions and more. Each title in the Essential Physical Science series explores a key curriculum topic. Find out how light and sound move. Which moves faster, light or sound? Why can't astronauts hear each other in space? Each book includes three simple activities or experiments to try. Heinemann Infosearch asks the questions you want answered. Each chapter starts with a question and provides a detailed answer. Book jacket.