D1-QRT30: CUBES BETWEEN POINT CHARGES-FORCE EXERTED BY ONE CHARGE ON THE OTHER In both cases, two equal and opposite charges are fixed in place a distance d apart. The cases are identical, except that in Case B an uncharged metal cube is placed between the two charges. +00 -Qo (a) Will the force exerted on the positive charge by the negative charge be () greater in Case A, (ii) greater in Case B, or (iii) the saine in both cases? Explain your reasoning. Case B + Uncharged -2o metal cube (b) Since the cube in Case B is metal, there will be electrons in it that are free to move around. What, if anything, will happen to those electrons? Explain your reasoning. Solution a) Force on both the charges will be same but in opposite direction. By Newton\'s law every action has equal and opposite reaction. F = Kq^2 / d^2 b) free electrons will move toward the positive charge and move away from negative charge because opposite charges attract and same charges repel. .

1. D1-QRT30: CUBES BETWEEN POINT CHARGES-FORCE EXERTED BY ONE CHARGE
ON THE OTHER In both cases, two equal and opposite charges are fixed in place a distance d
apart. The cases are identical, except that in Case B an uncharged metal cube is placed between
the two charges. +00 -Qo (a) Will the force exerted on the positive charge by the negative charge
be () greater in Case A, (ii) greater in Case B, or (iii) the saine in both cases? Explain your
reasoning. Case B + Uncharged -2o metal cube (b) Since the cube in Case B is metal, there will
be electrons in it that are free to move around. What, if anything, will happen to those electrons?
Explain your reasoning.
Solution
a) Force on both the charges will be same but in opposite direction. By Newton's law every
action has equal and opposite reaction.
F = Kq^2 / d^2
b) free electrons will move toward the positive charge and move away from negative charge
because opposite charges attract and same charges repel.