Question

What happens to the power of a bulb if it's broken filament is rejoined and lighted?

• A. More power is consumed in very less time.
• B. More power is consumed in longer time.
• C. The brigthtness will be lesser, usually for a short time, until the filament fails.
• D. The brigthtness will be more, usually for a longer time period, until the filament fails.

Answer 1

The correct option is A

More power is consumed in very less time.

The brigthtness will be more, usually for a short time, until the filament fails. This is because voltage exceeds, as the rejoined filament is shorter in length as the applied voltage is still the same. In other words, the resistance is lesser for shorter length resulting in more current, so more brightness. and after few seconds it melts again and circuit breaks. So more power is consumed in less time.