A ring of radius R has uniformly distributed charge. It spins about its axis with an angular velocity $\mathrm{\omega }$ . P is a point on its axis at a distance x, from its centre. The velocity of light in vaccum is c. Then the ratio of magnetic field to the electric field at P is equal to

• A

  $\frac{{\mathrm{x}}^2\mathrm{c}}{{\mathrm{R}}^2{\mathrm{\omega }}^2}$

• B

  $\frac{{\mathrm{xc}}^2}{{\mathrm{\omega R}}^2}$

• C

  $\frac{{\mathrm{\omega }}^2\mathrm{R}}{{\mathrm{x}}^2\mathrm{c}}$

• D

  $\frac{{\mathrm{\omega R}}^2}{{\mathrm{xc}}^2}$