question_answer

A particle having a mass of \[{{10}^{-2}}\,kg\] carries a charge of \[5\times {{10}^{-8}}C\]. The particle is given an initial horizontal velocity of \[{{10}^{5}}m{{s}^{-1}}\] in the presence of electric field \[\overset{\to }{\mathop{\mathbf{E}}}\,\] and magnetic field    \[\overset{\to }{\mathop{\mathbf{B}}}\,\] . To keep the particle moving in a horizontal direction, it is necessary that (1)  \[\overset{\to }{\mathop{\mathbf{B}}}\,\] should be perpendicular to the direction of velocity and \[\overset{\to }{\mathop{\mathbf{E}}}\,\] should be along the direction of velocity. (2) Both \[\overset{\to }{\mathop{\mathbf{B}}}\,\] and \[\overset{\to }{\mathop{\mathbf{E}}}\,\] should be along the direction of velocity. (3) Both \[\overset{\to }{\mathop{\mathbf{B}}}\,\] and \[\overset{\to }{\mathop{\mathbf{E}}}\,\] are mutually perpendicular and perpendicular to the direction of velocity. (4) \[\overset{\to }{\mathop{\mathbf{B}}}\,\] should be along the direction of velocity and \[\overset{\to }{\mathop{\mathbf{E}}}\,\] should be perpendicular to the direction of velocity. Which one of the following pairs of statements is possible?                               [AIPMT (M) 2010]

A)  (1) and (3)    

B)       (3) and (4)       

C)  (2) and (3)       

D)       (2) and (4)