An oil drop with mass $2.6 \times 10^{-15}\,\text{kg}$ and charge $-4.8 \times 10^{-19}\,\text{C}$ is situated in a vacuum between two horizontal plates. The plates are separated by $2.0\,\text{cm}$ and there is a potential difference (p.d.) of $1200\,\text{V}$ between them, as shown. Which statement best describes the motion of the oil drop?
- AIt is stationary.
- BIt has a downward acceleration of $9.7\,\text{m s}^{-2}$.
- CIt has an upward acceleration of $1.3\,\text{m s}^{-2}$.
- DIt has an upward acceleration of $11\,\text{m s}^{-2}$.