Every weekday morning, I'm awakened by the sound of my dad preparing for work in the bathroom next to my room. One of the most significant contributors to my awakening is his electric toothbrush (because its kinda loud). His electric toothbrush works because of magnetism and energy. The energy from the battery goes through a loop of wire on a pivot point. It then uses magnets to create a magnetic field across this loop. The loop has current inside it and because F= IlBsin⊖, the loop experiences forces on the left and right sides of the loop. This creates torque causing the brush part to rotate. This is also how motors work. My dad's electric toothbrush rotates one way and then switches directions periodically. This is probably due to the current being switched (alternating current) causing the force and torque to change directions.
