The force on a neutral dielectric object of biological interest in crossed time-varying electric and magnetic fields

Abstract

Externally imposed sinusoidal electric and magnetic fields acting ninety degrees out of phase and perpendicular to each other produce a unidirectional force on an object. The electromagnetic body force arising is found to be proportional to the frequency, to the field strengths, and to the (differential) polarizability of the body acted upon in its medium. The force is found to be small for practically realizable fields, but is different from that of the familiar “light pressure.” This “crossed field” force, based as it is upon the frequency-dependent relative effective dielectric constant and loss factor of the body as it moves in the supporting fluid medium, can provice spectra of various dielectric response mechanisms.