question_answer

  Two small balls having the same mass and charge and located on the same vertical at heights \[{{h}_{1}}\] and \[{{h}_{2}}\] are thrown in the same direction along the horizontal at the same velocity v. The first ball touches the ground at a distance \[\ell \] from the initial vertical. At what height \[{{H}_{2}}\]will the second ball be at this instant? The air drag and the effect of the charges induced on the ground should be neglected.

A) \[{{h}_{1}}+{{h}_{2}}-g{{\left( \frac{\ell }{v} \right)}^{2}}\]

B) \[{{h}_{1}}-{{h}_{2}}-g{{\left( \frac{\ell }{v} \right)}^{2}}\]

C) \[{{h}_{1}}+{{h}_{2}}-g{{\left( \frac{\ell }{v} \right)}^{1/2}}\]

D) \[\frac{{{h}_{1}}+{{h}_{2}}}{2}-g{{\left( \frac{\ell }{v} \right)}^{2}}\]