Angular Momentum of a Rotating Dipole

• Main Authors: Ahmad, Mohd Riduan, Mohd Esa, Mona Riza
• Format: Article
• Language: English
• Published: Penerbit UTeM 2014
• Subjects: QC Physics
• Online Access: http://eprints.utem.edu.my/id/eprint/12903/1/V06_N01_03.pdf; http://eprints.utem.edu.my/id/eprint/12903/; http://jtec.utem.edu.my

In this paper, we derive the far field electromagnetic fields of a rotating half-wave dipole antenna. Theoretically, we have demonstrated that the far electromagnetic fields of a rotating half-wave dipole carry angular momentum in the term of φ - φ′, which is absent from the stationary half-wave dipole antenna. The term sin(kr−ωt+[φ−φ']) tells us that the electromagnetic wave propagates outward with the speed of light c (evidence from k = ω/c) from the dipole along the r axis and both electric and magnetic fields are spinning (oscillate with ω rad/s) and orbiting (rotating with ω0 rad/s) along the r axis with the speed of light. The orbital frequency is evidence from the term φ−φ'=ω0t−ω0t'=ω0r/c