What should the working voltage of a capacitor be in relation to the highest voltage applied?

The correct answer emphasizes the importance of ensuring that a capacitor can handle voltage surges and fluctuations safely. A capacitor should ideally have a working voltage that is at least 50% greater than the highest voltage it will encounter in its operational environment. This margin is crucial for several reasons.

First, components in electrical systems can experience voltage spikes due to sudden changes in load or circuit conditions. If the capacitor is rated only for the same or slightly higher than the maximum voltage, there is a significant risk of failure under surge conditions, which could lead to catastrophic failure, overheating, or even explosion.

Additionally, capacitors can degrade over time, and their capacitance values can change with temperature and age. By ensuring that the working voltage is sufficiently higher than the maximum expected voltage, you provide a buffer that enhances the reliability and longevity of the capacitor.

In summary, having a working voltage that is at least 50% greater than the highest applied voltage helps to mitigate risks associated with voltage variations, ensuring that the capacitor operates efficiently and safely under varying conditions.