Question

It is said that two 60 W light bulbs shine brighter than three 40 W bulbs. Is it true?

Answer 1

The amount of brightness of bulbs depend on the amount of current which is passing through the filament of the bulb, as current increases the brightness also increases. They are directly proportional. For the same voltage, we can say that 60 W bulb will have higher current as compared to the 40 W bulb. (Power is product of current and voltage, when voltage is constant the current is directly proportional to the power). Hence we can say that 60 W bulbs are more brighter than the 40 W bulb (voltage is considered constant).