whats the difference between ac and dc electricity
Direct current
Direct current ( DC ) is the unidirectional flow of electric charge . A battery is a good example of a DC power supply . Direct current may flow in a conductor such as a wire , but can also flow through semiconductors , insulators , or even through a vacuum as in electron or ion beams . The electric current flows in a constant direction , distinguishing it from alternating current ( AC ) . A term formerly used for this type of current was galvanic current . 
Direct current ( DC ) is the unidirectional flow of electric charge . A battery is a good example of a DC power supply . Direct current may flow in a conductor such as a wire , but can also flow through semiconductors , insulators , or even through a vacuum as in electron or ion beams . The electric current flows in a constant direction , distinguishing it from alternating current ( AC ) . A term formerly used for this type of current was galvanic current .
Direct current (DC) is the unidirectional flow of electric charge. The electric current flows in a constant direction, distinguishing it from alternating current (AC).
Direct current ( DC ) is the unidirectional flow of electric charge . The electric current flows in a constant direction , distinguishing it from alternating current ( AC ) .