 ### Biography

Musa D Abdullahi obtained his BSc degree in Physics from the University of Manchester, England, 1965. He was the first person to obtain a Postgraduate degree in
Electronics and Telecoms from Ahmadu Bello University, Zaria, Nigeria in August 1968. He taught at Ahmadu Bello University, Zaria and Federal University of Technology
Minna in Nigeria. He is a Fellow of the Nigerian Academy of Engineering. He retired from public service in August 2000. He is now an Adjunct Lecturer in the Department
of Physics, UMYU, Katsina, Nigeria. He is a prolific contributor of papers in online journals.

### Abstract

This paper assumed that the charge and mass of a particle are independent of its speed relative to an observer. A moving
particle of charge Q and mass m with an electrostatic field Eo at an angle θ to the direction of speed v is considered. The
intrinsic energy of the particle is contained in its electrostatic field. The magnetic field generated takes no energy. It is shown
that, as a result of aberration of electric field Eo, becomes a dynamic electric field Ev displaced by aberration angle α from
the stationary position. Equating the difference between the energy of dynamic field Ev and the energy of electrostatic field
Eo, with the kinetic energy ½ mv2 of the particle, gives a mass-energy equivalence law as E = ½ mc2. It is also shown that a
charged particle moving at time t with acceleration dv/dt produces a reactive electric field Ea = -μoεoφ(dv/dt), where μo is the
permeability and εo the permittivity of space and φ the potential at a point due to the charge. It is proposed that Ea acts on the
same charge Q producing it, to create a reactive force equal and opposite to the accelerating force, so that EaQ = -μoεoφQ(dv/
dt) = -2Eμoεo(dv/dt) = -m(dv/dt), where E = φQ/2 = ½ mc2 is the electrostatic energy and c2 = 1/μoεo, c being the speed of light.
The reactive field Ea explains the cause of inertia of a body as an electrical effect in the body.