Electrostatic Induction in Grounded Conductors

Steps:

• Positive charge on plate X generates an electric field directed toward plate Y.
• This field repels protons in Y toward its far side and subsequently to earth via the ground connection.
• The field also repels electrons in Y, causing them to flow to earth to balance the repulsion.
• Grounding allows both charge types to flow from Y to earth, maintaining Y's initial uncharged state.

Why B is correct:

• By Coulomb's law, like charges repel, so the positive field from X repels both protons and electrons from Y to earth, ensuring zero net charge on Y.

Why the others are wrong:

• A: Ignores proton flow; both charges move.
• C: Electrons flow from Y, not to Y.
• D: Protons flow from Y, not to Y.

Final answer: B