Interactions between Electricity and Magnetism Interactions between electricity and magnetism all involve some motion of either charges (electricity) or changes in the magnetic field.

Magnetic Force  Magnetic Force  There is a magnetic force whenever a charge (or charged object) moves across a magnetic field.  The equation for this is F = q v B  q = amount of charge (C)  v = velocity  B = magnetic field (Teslas)

Right Hand Rule #1  Extend your thumb, it’s the direction of the current.  Point fingers in direction of the Magnetic Field, B. (Fingers = field lines)  Orient your palm so it’s the direction of the force (Palm Push)  This force happens only when the charge moves perpendicular to the magnetic field B.

Right Hand Rule #2  To determine the direction of the circular magnetic field around a wire carrying a current.  Direct your thumb along the wire in the direction of the current.  Your fingers curl in the direction of the circular magnetic field.

Mag/Elec Interactions  Electro-magnets  If you coil a wire into a helical form (like wrapping a wire around a cylinder) and run a current through it, each circular coil creates a small mag field.  The mag field from each coil “adds up” to create what looks like a magnet with a North and South pole.  By running a current through this wire, you “make” a magnet. This is also known as a solenoid.