Final answer:
The question pertains to a physics concept involving a capacitor being charged in an electrical circuit. The voltage across the charged capacitor, given the charge and capacitance, is calculated using the formula voltage equals charge divided by capacitance.
Step-by-step explanation:
The question deals with the charging of a capacitor in a simple DC circuit. When the switch in the circuit is closed, a battery is connected to a resistor and an uncharged capacitor, starting at t = 0 s, current begins to flow, and the capacitor starts to charge.
The current will decrease over time as the capacitor charges until it reaches its maximum charge, where the current will be zero and the voltage across the capacitor will be equal to the emf of the battery. The question specifies that after several seconds, the capacitor plates are charged to ± 30 μC (microcoulombs), and given the capacitance is 10 μF (microfarads), we can calculate the voltage across the capacitor.
To find the voltage across the capacitor (V), we use the formula V = Q/C, where Q is the charge on the capacitor, and C is the capacitance. Plugging in the values, we get V = 30 μC / 10 μF = 3 volts.