Final answer:
The initial charge on a capacitor is zero until a potential difference is applied across its plates, which will cause charge to accumulate according to the Q = CV relationship.
Step-by-step explanation:
The initial charge on a capacitor is typically zero. Before a capacitor is connected to any voltage source, there's no potential difference across its plates, and therefore no charge accumulation. The charge only begins to accumulate once a voltage is applied, like in the described simulation where a variable-voltage battery is connected to a parallel-plate capacitor and the slider is moved from zero volts. This process aligns with the formula Q = CV, where 'Q' represents the charge stored in the capacitor, 'C' is the capacitance, and 'V' is the voltage across the capacitor. The charge is dependent on the voltage applied and capacitance of the capacitor. The answer to the question of what is the initial charge on the capacitor is zero.