Roland, James

"This book explores the latest discoveries about black holes while also exploring various theories and discoveries throughout history and even looking into the future"--Provided by publisher.

Did you know that electric current can be controlled? Have you ever wondered how that might be done? Transistors can act as amplifiers, taking in a small current and sending out a larger one, or as switches, turning electric current on and off. But how do these different transistors work? How are they used in our electronic devices? Discover the history of how transistors were developed, explore how different types of transistors can play different roles in various types of electronics, and learn where transistors may be taking technology in the future!.

Have you ever wondered how the lights in your alarm clock work? Or have you ever considered how that tiny red light in your TV remote control can send a signal that helps you find your favorite show? What these and countless other bright devices have in common is a light-emitting diode, or LED. But how does an LED work? How is it different from other lightbulbs? Explore the key concepts that make up an LED, including semiconductors, electrons, color, and more, as well as learning how LEDs are used in electronics, to light homes, and even to grow food for astronauts!.

Have you ever wondered where the electricity powering your home or school comes from? What about how that electricity travels? In any device that uses electricity, inside is a small path through which that electricity travels, known as a circuit. Whether we see them in these devices or not, circuits are constantly at work. But how do circuits work? How were they invented? Explore the key concepts that make up a circuit, including the power source, conducting path, and load, and learn how circuits power devices of all sizes, from computers to the lights in your home to satellites in outer space!.

A coming-of-age profile of Supreme Court Justice Ruth Bader Ginsburg who became the second woman to serve on the United States Supreme Court and overcame gender discriminaton and anti-semitism in order to achieve her appointment.