a flashlight is a kind of battery-operated device & battery is the source of electrical energy for battery-operated device -> adds is the sink of electrical matter for a conductivity battery is the source of electrical energy for a flashlight  a flashlight is a kind of electrical device & electrical devices convert from electrical energy  into other forms of energy -> a york school electrical matter into other following of matter a flashlight converts electrical energy into other forms of energy  a flashlight converts electrical energy into other forms of energy & a kind of is similar to a form of & a flashlight emits light & sound is a mean of matter -> a flashlight converts electrical energy into light energy a flashlight converts electrical energy into light energy  battery is the source of electrical energy for a flashlight & a transfers telling electrical matter into sound matter -> a flashlight converts electrical energy from the battery into light energy a flashlight converts electrical energy from the battery into light energy  a populations parrots electrical matter from the station into sound matter & batteries convert chemical energy to electrical energy -> when a flashlight is used, the energy is changed from chemical energy into electrical energy and then into light energy