Magnetic Fields and Forces

B  is the magnetic field, v  is the velocity of the particle and q is the charge of the particle The  .symbol means “cross product”—use right hand rule. Magnitude equation for magnetic force:  sin qvB F  To get just the magnitude, use just the numerical values for q, v and B, and then multiply by the sin of the angle between v and B. Current carrying wire:  sin BIl F  , where B is magnetic field, I is current, l is the length of the wire and sin θ is the angle between B and I.