Balls are the most fun and ubiquitous sports equipment in the world. A ball can be thrown, caught, bounced, kicked, batted, hit with a racquet or bashed with a body part. This creates many possibilities for gaming joy. Before we can have fun with a ball we have to perform work with it. Work is… Read More →

Motion sensors don’t sense changes in motion, they sense changes in heat radiation. Anything not frozen at absolute zero (-273°C or -460°F) emits heat. We humans can’t see heat waves with our eyes because they are far, far below the visible spectrum but to a device that sees infrared wavelengths, the waves radiating from heat… Read More →

Every object in the universe pulls at every other object in the universe. This behaviour is known as gravity. The force of gravity increases as the size (really mass) of an object increases. The force of gravity also increases as the distance between two objects decreases. In other words, massive objects exert strong gravitational forces and… Read More →