We know the conservation of energy, mass, and momentum are cornerstones of science. We have studied the 'Law of conservation of angular momentum' in school physics. It also holds some surprising facts. We will see them now.
Momentum is the product of mass and velocity. Angular momentum is the product of the 'moment of inertia' and angular velocity. The moment of inertia plays the role of mass in a circular motion. It is roughly the product of rotating mass and its distance from the axis of rotation.
Hence
Angular momentum = Moment of inertia* angular velocity = constant
or
Mass * distance from axis*angular velocity = constant
In the above formula, if one quantity increases, another quantity must decrease to keep the product constant.
A dancer on an ordinary floor or ice floor sometimes spins herself. If she out-stretches her arms, she will spin slowly. If she brings her arms close to her chest, she will spin rapidly. Here moment of inertia is disturbed and hence speed also is disturbed.
Earth goes around the Sun in an elliptical orbit. When the earth is away from the sun, it moves slowly. (Remember, the sun is situated at one of two foci (centers) in the ellipse). When the earth is close to the sun, it goes fast. Again, it happens to conserve the angular momentum.
Assume, a man is sitting on a freely rotating lightweight chair. He is also holding a rotating bicycle wheel. Initially he holds it vertically. So there is only vertical rotations initially and no horizontal rotations. Suppose, the man suddenly turns the wheel to the horizontal position, the wheel rotates horizontally. But there were no horizontal rotations initially. And the system has to conserve the angular momentum. So the chair begins to rotate in opposite direction to that of the wheel horizontally. Consequently, the total rotations or total angular momentum (+momentum and - momentum) is zero and conserved. It is clearly illustrated in the animated picture.
So new rotations are created due to conservation of angular momentum. It will be possible to create new energy using the law of conservation of energy.
Also we should be able create new mass or particle because of conservation of mass. Suppose, we create electron from nothing, positron will also be born to nullify it. Similarly neutrino and anti- neutrino.
Another interesting fact about the momentum. There is festival cracker or bomb. Before lighting it up, its total momentum is zero. Once it is ignited, it explodes and fragments are thrown in all the directions. Again the total momentum of all the fragments is zero. The directions of fragments must be taken into account.
As the rocket goes up, used stages in the rocket is thrown into space one by one to reduce the mass. As the mass of the rocket reduces, the speed of the rocket goes up to keep the momentum constant.
So speed is created without using fuel.
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