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Uncharged capacitor is connected in a series with a resistor, switch, and battery . When the switch is closed the potential drop across the resistor:

Correct answer: B. Initially maximum then decreases to zero

  • A. Remains the same
  • B. Initially maximum then decreases to zero
  • C. Becomes zero then increases to maximum
  • D. Remains zero

Explanation

When an uncharged capacitor is connected in series with a resistor and a battery, and the switch is closed, the circuit allows maximum initial current to flow, resulting in a maximum potential drop across the resistor. This is because the capacitor initially behaves like a short circuit. As the capacitor charges, the current decreases exponentially over time, causing the potential drop across the resistor to decrease until it eventually becomes zero when the capacitor is fully charged. This behavior is described by the equation V = IR, where V is the potential drop, I is the current, and R is the resistance. The other options are incorrect because they do not accurately describe the variation of potential drop as the capacitor charges.

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Electrostatics describes forces between charges through Coulomb's law, electric fields and field intensity, then uses electric potential to measure energy per unit charge. Capacitors store charge and electrical energy, with capacitance depending on geometry and dielectric material, not simply on the amount of charge present.

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