# A particle of mass $1 \times 10^{-26}\;kg$ and charge $1.6 \times 10^{-19} C$ travelling with a velocity $1.28 \times 10^{6} ms^{-1}$ along the positive X-axis enters a region in which a uniform electric field $\overrightarrow {E}$ and a uniform magnetic field of induction $\overrightarrow {B}$ are present. If $\overrightarrow {E} =-102.4 \times 10^3 \hat k NC^{-1}$ and $B= 8 \times 10^{-2}\; \hat j Wbm^{-2}$, the direction of motion of the particles is :

(a) along the positive X-axis (b) along the negative X-axis (c) at $45^{\circ}$ to the positive X-axis (d) at $135^{\circ}$ to the positive X-axis

(A) along the positive X-axis
Hence A is the correct answer.