the generator effect

• electricity is made by the generator effect
• the generator effect - the induction of a potential difference in a wire which is moving relative to a magnetic field, or experiencing a change in magnetic field
• moving a wire up through a magnetic field causes a potential difference to be induced across the wire . when the wire stops moving, potential difference is lost
• moving wire back and forth causes potential difference to reverse direction. this is the induced potential
• if we have a complete circuit then we induce a current . direction of current switches when direction of movement switches. movement stops then current stops
• the induced potential difference and current is larger if

  we use a stronger magnetic field

  we move the wire more rapidly

  greater number of turns in coil
• a magnet moving in and out of a coil of wire induces a induced current. current changes when direction of movement changes. also switch direction of current by switch poles of the magnet.
• however, this induced current creates its own magnetic field. this magnetic field opposes the movement of the magnet. the north pole of magnet and magnetic field repel from each other, making magnet harder to push in. when in they attract, making harder to pull magnet out. this does work. transfers energy from movement of magnet to movement of current