- A pair of parallel conducting plates are separated by 50cm. The electric potential of one plate is +200V and the electric potential of the other plate is +450V. A proton travels from the +200V plate to the +450V plate.
What is the electric field strength between the plates and the change in the kinetic energy of the proton?

| Magnitude / NC⁻¹ | Change in kinetic energy | |
|---|---|---|
| A. | 500 | positive |
| B. | 500 | negative |
| C. | 900 | positive |
| D. | 900 | negative |