Derive the formula for the force acting on a charged particle moving in a magnetic field.

The force acting on a current-carrying conductor placed in a magnetic field is,
F = B × I × L
The current I is the rate of flow of charge.
Now, if a charge Q flows in time t then the current I = Q/t. Hence substituting for I in
the above equation, we get,
F =
Suppose the particle carrying the charge Q travels a length L in time t, then the velocity
v = L/t. So substituting this value, we get
Force on moving charge F = B × Q × v.