A particle of mass m and charge +q is projected from the origin with a speed v at an angle $\;30^{0}\;$ with the horizontal into an electric field of intensity E directed downward . Equation of trajectory of particle is . Neglect gravity

Question

$(a)\;y=\large\frac{x}{\sqrt{3}}+\large\frac{2}{3}\;\large\frac{qEx^2}{mv^2}\qquad(b)\;y=x \sqrt{3} +\large\frac{2}{3}\;\large\frac{qEx^2}{mv^2}\qquad(c)\;y=\large\frac{x}{\sqrt{3}}-\large\frac{2}{3}\;\large\frac{qEx^2}{mv^2}\qquad(d)\;y=x \sqrt{3} -\large\frac{3}{2}\;\large\frac{qEx^2}{mv^2}$