A charged particle moves uniformly on the xy-plane along a circle of radius a centred at the origin. A detector is put at a distance d on the x-axis to detect the electromagnetic wave radiated by the particle along the x- direction. If d >> a, the wave received by the detector is
1
unpolarised
2
circularly polarized with the plane of polarization being the yz-plane
3
linearly polarized along the y-direction
4
linearly polarized along the z-direction