 Welcome back to Kids Fun Science. My name is Ken. Today's experiment is the bicycle wheel gyroscope, the wonders of physics. As always, adult supervision is required. What you need for this experiment is a lazy Susan or a spinning chair, a bicycle wheel, handles, and a volunteer. Welcome back to Kids Fun Science. My name is Grace. Today's experiment is the spinning wheel. What we have here is a bike tire with handles. And then we have a lazy Susan that I used in another one that will spin. And then what we're going to do is we're going to, I'm going to get the wheel to go and then the angular momentum. When you turn it, it will spin you in a circle, right? So let me get the wheel to go and then you got a hold of it. Oh, sorry. And don't hold it near your chest or belly. Okay. Now, when you turn it sideways, the angular momentum pulls you around, right? Isn't that cool? Now you turn it the other way. Change directions. Isn't that a weird feeling? So you're controlling it because of the angular momentum of the tire. And then you can stop it if you go straight, right? You got it. A rotating bicycle wheel has angular momentum, which is the property involving the speed of the rotation, the mass of the wheel and how the mass is distributed. For example, most of a bicycle wheel's mass is concentrated along the wheel's rim rather than the center. And this causes a large angular momentum with a given speed. Angular momentum is characterized by both size and direction. Since Grace is standing on a lazy Susan with a bicycle wheel spinning, one way to change the angular momentum of the bicycle wheel is to change its direction. To do this, Grace must exert a twisting force, which is called a torque, on the wheel. The bicycle wheel will then exert an equal and opposite torque on Grace. That's because every action there is is equal and opposite reaction. Thrust when Grace twists the bicycle wheel, the bicycle wheel will twist Grace the opposite way. Since Grace is standing on a low friction pivot and twisting force of the bicycle wheel will cause Grace to turn, the changing Grace's angular momentum compensates for the change in the angular momentum on the wheel. The system as a whole ends and obeys the principle and the conservation of angular momentum. This time I suspended the bicycle wheel with one of its ends by a rope and then hung it from the top of the patio and gave it a really hard spin. This seems to defy gravity as the torque is created by the spinning wheel and it counteracts the torque due to gravity. This is also known as gyroscopes and they've been used through history and various uses such as stabilizing spacecrafts and guidance for systems like ships and missiles. All right, well thanks for watching and remember to click thumbs up which you can't do and to subscribe.