But Why is a show led by kids. They ask the questions and we find the answers. It’s a big interesting world out there. On But Why, we tackle topics large and small, about nature, words, even the end of the world. Know a kid with a question? Record it with a smartphone. Be sure to include your kid's first name, age, and town and send the recording to questions@butwhykids.org!
Why does green mean go and red mean stop?
Why is there traffic? How do traffic lights work? How do they know when to turn red and green? Why does green mean go and red mean stop? Why are cars able to go faster than they are allowed to go with the speed limit? Why do we drive on the right side of the road in the United States? Why are some roads bigger than others? Answers to your traffic questions with Mike Knodler, professor and director of the Transportation Center at the University of Massachusetts.
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