Episode 2

S3 E2: ASH MINERALS - Michael holds a piece of newspaper with tongs over a candle. After the paper has burned, Mr. Wizard explains what is left behind are the minerals. MOLD - This invasion can start from one tiny spore, so small it's invisible. If the conditions of temperature and moisture are right, the invader can spread a network of filaments across its food. The invader can grow thousands of round spore cases that split apart to release millions of spores. That's what happens when a slice of bread is invaded by the plant you call a mold. OSCILLOSCOPE TIMER - With a flash camera Mr. Wizard takes Leila's picture. They are going to measure the duration of the flash with an oscilloscope. SUGAR CRYSTALS - Mr. Wizard shows Jason how to make sugar crystals. WHAT IS THIS ? - You no doubt have held this common mystery object in your hand many times, but you probably have no idea when. It's not a donut, but much, much smaller. It's the shell of a tiny marine animal. They grow together to form ball‑like dwellings for underwater plants. What is this? SPOOL ROLL - Mr. Wizard shows Darren a spool of ribbon. He pulls on the ribbon and the spool rolls forward. Then he pulls on the ribbon at a different angle. The spool rolls in the opposite direction. Mr. Wizard explains that when you pull at a fairly high angle, you are putting pressure on the spool above the center line and that makes it roll forward. At a lower angle, you are putting pressure on the other side which makes the spool roll in reverse. UNDERWATER PARK - You may have been to many parks, but you probably haven't been to a park like this one. It's all underwater. At the John Pennekamp Coral Reef State Park just south of Miami, Florida, scientists and amateur and professional divers can explore at the bottom of the sea. They use all sort of equipment, including mini submarines. RADIOMETER CHALLENGE - After watching the spinner inside a radiometer turn clockwise, Mr. Wizard challenges Nicola to make it go in the opposite direction. They discuss how heat radiated into the partially‑evacuated glass sphere is absorbed by the black sides of the spinner. The heat speeds up the air molecules next to the black sides giving them a push. As a result the spinner moves in a clockwise direction.