Solution:
If the speed of the particle in circle varies, it is αr example of non-uniform circular motion A roller coaster car that slows down and speeds up as it moves around vertical loop. The radial component of acceleration αr=v2r which is perpendicular to the instantaneous velocity still acts and is directed towards the center of the circle . Since speed has different value at different points in the motion, the value of αrαd is not constant. Radial acceleration is greatest at the point in the circle where the speed is greatest. In non- uniform circular motion there is also a component of the acceleration that is parallel to the instantaneous velocity This is the component α|| or αtangential.i.e tangent to the circle , αtangential is equal to rate of change of speed . Thus αrad=v2randαtangential=d|v|dt.
