Can they give any harm to the body health?
Quartz has the peizoelectric property,which was first found out by a natural explorer while travelling in forests of Africa.The property means that when a current is applied to quartz,it moves, vice-versa.The battery supplies the current it moves the piece of quartz inside a clock,which moves the machinery in a clock.Quartz has now replaced the mechanical automatic spring winding systems,which was in vogue earlier.
