Do sparks fly when you pull your jacket off? Do you get a crackling shock when you touch a doorknob? These things happen because you've been collecting electricity! The sparks and crackles are...
What is electricity?
When you turn on a light, ring a doorbell, or plug in a coffee pot, you start a parade---but it's a parade you can't see! The parade is a parade of moving, pushing electrons (ih trahnz). The energy...
Currents and Sparks
Currents and Sparks Currents and Sparks
Putting light to work
What's on TV tonight? Why, nothing but thousands of lines full of millions of spots of light. That's what makes up the program you are watching! Part of a TV camera makes an electric copy of the...
Stand-out pictures
The pages in this book are flat and smooth. So are the pictures on the pages. But if you look at the picture pairs on the opposite page in a special way, the things in them will seem to stand out...
Round and flat
Special pictures called holograms make things look real. When light shines through the film, you see the pictured thing from all sides. Your dog was chasing a big red ball when the picture was...
Superlight!
It punches through steel. It carries complicated messages. It performs tiny, delicate operations. Anything that can do many kinds of work should be magic. But this isn't magic---it's a special kind...
Lamp Number 9
Tom Edison sat in his laboratory, watching an assistant light the gas lamps. The sight always bothered him. For years he had been convinced that electricity could be used to make light---a light as...
Eyes for machines
Sometimes only a few people get on and off the elevator. Sometimes lots of people get on and off. But the elevator always seems to know how long to stop. The door doesn't close until the last person...
Seeing things that aren’t there
Can a lake vanish? A few minutes ago you saw cool water shimmering just up the road ahead of the car. But now all you see is miles of hot paved highway. Where is the lake? The disappearing lake is a...