Robots, Hot Air Balloons and more

S1 E5: HOT AIR BALLOON - Scott and Jason prepare to launch a hot air balloon made of paper. The launcher is a stove pipe with a base of bricks. Mr. Wizard instructs Scott to light the newspaper inside the brick base. Jason holds the balloon open over the top of the cylinder. As the air inside the balloon is heated, it weighs less than an equal volume of cooler air. Gravity pulls the colder air down and the warmer air is forced upward carrying the balloon along with it. NYC to TOKYO - Tanis is asked to select the shortest route from New York to Tokyo and determine if it would go over California, British Columbia, or Alaska. She says it looks like the shortest route would be over California, but says she took a trip with her father from Calgary to Germany and flew over Greenland. She's not sure why. Mr. Wizard explains that the wall map is a Mercator projection that distorts areas. WHISPERING TUBE - Mr.Wizard speaks through a paper tube and says: Now hear this. Now hear this. Billy recognizes it as a message on a ship and assumes tubes are used in case microphones are knocked out, they can still communicate. HERO’S HAND - Leila is introduced to Hero, a robot designed to teach robotics. Mr. Wizard asks her if she'd like a glass of milk. Hero has been programmed to serve it. Leila pushes a button on the robot. It picks up a glass of milk, turns to Leila, and sets the glass down in front of her. Leila says: Thank you. ROBOTS IN THE FACTORY - Watch this welder at work. Each weld will be exactly in the right place and its all done by a machine with no one at the controls. That is one definition of a robot. How does it know exactly where each weld is supposed to be? OPTICAL ILLUSION - Mr.Wizard has drinking straws lined up on the table and asks Stacey to pick the longest. She assumes they are the same length. He cautions her that he expected she would know about optical illusions and so could fool her. He points out he could have cut off one of the straws. She thinks he is simply trying to trick her. She uses another straw to compare the two in the illusion. She finds one straw much shorter than the other. I-BEAM - Michael is to be an engineer and build a bridge over an imaginary river between two bricks using three pieces of wood. He puts a single piece of wood between the bricks. It sags when he steps on it. He adds strength with a second and then the third piece of wood. The bridge still sags. Mr.Wizard explains I-Beams.