Every What If? Lab
Big questions about nature, space and machines. Change the rules, make a prediction and see what happens.
- Every lab 349
- Experiments you can run 149
- Space and astronomy 60
- Earth, weather and climate 55
- Physics and motion 50
- Animals, plants and ecosystems 45
- Chemistry and materials 30
- Machines and engineering 29
- Human body and biology 25
- Energy and electricity 25
- Oceans and water 20
- Technology and future possibilities 10
349 to explore · page 8 of 8
- Watch Try it What If? Lab What if you threw a ball from a cliff? On flat ground, a ball launched at 45° goes farthest. Put the same launcher on top of a 20-meter cliff in our model and the ball flies longer and farther, and the best angle drops to about 31°. Find out why extra height changes the best aim.
- Watch Try it What If? Lab What if you tossed a ball straight up? A ball tossed straight up slows down, stops for a split second at the top, then falls back. In this lab you toss it at 8 meters per second and watch its speed. Here is the surprise: it comes back past your starting point just as fast as it left.
- Watch Try it What If? Lab What if you tried to swing in space? A swing is a pendulum: gravity pulls the seat back down to the middle every time it rises. In our model, a swing with 2-meter ropes takes about 2.9 seconds to go there and back on Earth. Switch gravity off and the seat simply stays where you let it go.
- Watch Try it What If? Lab What if you turned the heating down a little? A warm house leaks heat faster than a cooler one. In our model, turning the thermostat from 20 °C to 18 °C on a 0 °C day cuts the heat the house needs by a tenth, from about 86 to about 78 kilowatt-hours a day. On a mild day, the same two degrees save an even bigger share.
- Watch Try it What If? Lab What if you used a parachute on Mars? A parachute works by pushing against air. Mars pulls more gently than Earth, but its air is extremely thin. In our model, a 10-kilogram box under a parachute lands at about 8 meters per second on Earth but about 18 on Mars, barely slower than with no parachute at all.
- Watch What If? Lab What if you visited an icy moon? Jupiter's moon Europa and Saturn's moon Enceladus are covered in ice, but scientists think salty oceans lie underneath. The squeezing pull of their giant planets keeps the insides warm. Imagine walking on the ice, peeking at the ocean below and joining the search for places where life could exist.
- Watch Try it What If? Lab What if your arm muscle joined farther from your elbow? Your forearm works like a lever, with your elbow as the pivot. Your biceps muscle pulls on it just a few centimeters from the elbow, so it has to pull much harder than the weight in your hand. Move the muscle's attachment in a lever model and discover the trade between strength and speed.
- Watch Try it What If? Lab What if your cocoa went in a flask? A mug of hot cocoa cools fast: in our model it drops from 80 °C to 60 °C in under 12 minutes. Pour the same cocoa into a vacuum flask and it takes about 100 minutes. Find out how a flask blocks the three ways heat escapes.
- Watch Try it What If? Lab What if your eyes were underwater? The clear front of your eye, the cornea, does most of its focusing by bending light as it passes from air into the eye. In this lab, shine a beam from air into an eye-like material, then from water into it, and see the bend almost vanish. That's why things look blurry when you open your eyes underwater.
- Watch What If? Lab What if your heart were as small as a mouse’s? A resting mouse's heart can beat more than 550 times a minute; yours beats about 60 to 100 times. A blue whale's heart has been measured as slow as 2 beats a minute. Explore why small animals have racing hearts and big animals slow ones, and why your heart is just the right size for you.
- Watch What If? Lab What if your house made its own power? An average American home used about 900 kilowatt-hours of electricity a month in 2022. Some homes make part of it themselves with solar panels on the roof, store some in a battery for the evening, and use a heat pump to warm the house. Follow each idea to see what it could do, and what it can't.
- Watch Try it What If? Lab What if your legs were as long as a giraffe’s? When you walk, each leg swings forward like a pendulum hanging from your hip. Longer pendulums swing more slowly. A giraffe's legs are about 1.8 meters long. Make a model leg twice as long and find out how much slower it swings, and why long legs still cover ground faster.
- Watch What If? Lab What if your skin could make food from sunlight? Plants catch sunlight and turn it into food, a process called photosynthesis. Imagine if your skin could do the same. Would you be able to skip meals? We'll compare how much energy your body needs with how much sunshine could give, and meet a real sea slug that keeps borrowed plant parts working inside its body.