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What If? Lab What if you played catch on a merry-go-round? Roll a ball straight across a spinning merry-go-round and, to the riders, it seems to curve away. Someone standing on the ground sees it go straight. The same trick, on our spinning Earth, bends winds and makes big storms swirl.
What If? Lab What if a turbine had a small generator? A wind turbine's blades catch the wind, but its generator turns that spin into electricity, and every generator has a top limit called its rated power. In our model, big blades in a strong wind make about 2.13 megawatts with a large generator. Swap in a 1-megawatt generator, and the turbine can never make more than 1 megawatt, however hard the wind blows.
What If? Lab What if a wind turbine had different blades? A wind turbine's blades sweep out a big circle, catching the wind that blows through it. Make the blades twice as long and the circle holds four times as much wind. In our model, that turns about 1.2 megawatts of electricity into about 4.9 megawatts, in the same wind. Find out why wind turbines keep getting bigger.
What If? Lab What if sharks disappeared? Sharks catch and eat other sea animals, and just having them around changes where those animals go. Follow what scientists have found in Australia's Shark Bay seagrass meadows and on coral reefs, where the evidence is still debated, and how some shark populations are recovering.