Even though an electric field E exerts a force qE

Question:

Even though an electric field E exerts a force qE on a charged particle yet the electric field of an EM wave does not contribute to the radiation pressure. Explain.

Solution:

Even though an electric field E exerts a force qE on a charged particle yet the electric field of an EM wave does not contribute to the radiation pressure because radiation

pressure is the result of the action of the magnetic field of the wave on the electric currents which is induced by the electric field.