An electron with a kinetic energy of 100 eV enters the space between the plates of plane capacitor made of two dense metal grids at an angle of 30° with the plates of capacitor and leaves this space at an angle of 45° with the plates. What is the potential difference of the capacitor:
Correct answer: B. 50 V
- A. 100 V
- B. 50 V
- C. 150 V
- D. 200 V
Explanation
To find the potential difference of the capacitor, consider the change in the electron's kinetic energy as it moves between the plates. The initial kinetic energy is 100 eV, and as the electron exits at a different angle, its velocity component perpendicular to the plates has changed, indicating a change in potential energy. By using the energy conservation principle, the potential difference can be calculated as 50 V. The other options do not correctly account for the change in kinetic energy and the resulting potential difference.
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