An electromagnetic wave travelling in $x$-direction is described by field equation $\mathrm{E}_y=300 \sin \omega\left(t-\frac{x}{\mathrm{c}}\right)$. If the electron is restricted to move in y -direction only with speed of $1.5 \times 10^6 \mathrm{m} / \mathrm{s}$ then ratio of maximum electric and magnetic forces acting on the electron is $\_\_\_\_$ .