Component used within mobile's?

Question

What is the principle/vibrator and technik used in mobile phones that provides for the vibrations when the muted "vibration alert" mode is enabled?

Answer 1

it is a miniture motor that has an ecentric, weighted cam on its shaft.  the vibration is a result of the severe imbalance to rotation. its like being in a  car whose tires are out of balance at 60 mph.