Build your own model of a fusion reaction: start with a regular red lego (a proton). Wrap a rubberband around it to be the strong nuclear force. Then connect a small blue lego (an electron) to [...]
Make a bunch of paper balls One atom of uranium has 92 protons and about 145 neutrons in its nucleus. So make 92 small balls of paper... no, that would be too [...]
The ballet dancer Misty Copeland jumps high by pushing off the floor. As with the First and Second Laws of Motion, an Islamic scientist was the first to propose the [...]
How hard will the ball hit the catcher's glove? It depends how big the ball is. how fast the pitcher throws it, and how far away the catcher is. Like [...]
Isaac Newton, mathematician and physicist About 1000 AD, in the Islamic Empire, Ibn Sina came up with the idea that an object moving in a vacuum would just keep moving forever without slowing [...]
Light takes years to reach us from these stars far away in space. When solid objects move through space, they follow certain rules that let us predict how they will act. We call [...]
Pedaling will make her accelerate. So will going downhill. Acceleration is a way to measure how fast something is speeding up. Suppose you are riding your bike. You start out [...]
Ancient Egyptian cattle plowing (Louvre Museum, Paris) You might think you know what work is, like homework, or having to pick up your room, right? But to scientists, work has [...]
An Egyptian potter uses a pottery wheel, about 2000 BC. He uses his hand to spin the wheel. Wheels do not exist in nature, and no animals use them except [...]
What is a wedge? This stone hand-ax from Chennai, India is a kind of wedge. A wedge is a kind of inclined plane What is a wedge? Like screws, wedges are [...]
