When the speed changes along a circular path, two acceleration components exist simultaneously:

Centripetal (radial): a_c = v^2/r (toward centre, always present) Tangential: a_t = dv/dt = d|v|/dt (along the tangent, only when speed changes)

Net acceleration: a_net = sqrt(a_c^2 + a_t^2) Angle with radius: phi = arctan(a_t/a_c)

Key point: The net force is NOT directed toward the centre in non-uniform circular motion. It has both radial and tangential components.

Angular kinematics (constant alpha): omega = omega_0 + alphat theta = omega_0t + (1/2)alphat^2 omega^2 = omega_0^2 + 2alphatheta