In U.C.M,the direction of velocity is along a tangent drawn to the position of particle on circumference of circle. Hence the direction of velocity goes on changing continously; however the magnitude of velocity is constant. Hence the magnitude of angular velocity is constant.
Thus, Uniform Circular Motion (U.C.M) can also be defined as periodic motion of a particle moving along circumference of a circle with constant angular speed.
Eg. 1)Motion of the earth around the sun. 2)Motion of the moon around the earth.
In U.C.M., speed, radial acceleration,kinetic energy, angular momentum, magnitude of linear momentum remain constant.
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