When an electric charge q is moving with velocity \(\vec v\) in the magnetic field \(\vec B\), it experiences a force, called magnetic force \(\vec F_m\) . After careful experiments, Lorentz deduced the force experienced by a moving charge in the magnetic field \(\vec F_m\).
\(\vec F_m\) = q \((\vec v \times \vec B)\) ......... (1)
In magnitude, Fm =qvB sin θ ……. (2)
The equations (1) and (2) imply
1. \(\vec F_m\) is directly proportional to the magnetic field \(\vec B\)
2. \(\vec F_m\) is directly proportional to the velocity \(\vec v\)
3. \(\vec F_m\) is directly proportional to sine of the angle between the velocity and magnetic field
4. \(\vec F_m\) is directly proportional to the magnitude of the charge q
5. The direction of \(\vec F_m\) is always perpendicular to \(\vec v\) and g as \(\vec F_m\) is ti’e cross product of \(\vec v\)and \(\vec B\)
6. The direction of jprn is on negative charge is opposite to the direction of F charge provided other factors are identical.
7. If velocity v of the charge q is along magnetic field \(\vec B\) and then, \(\vec F_m\) is Zero .
