The Photoelectric Effect

Recently, superstar Elon Musk with his brother successfully have propelled their company ‘SolarCity’ to be the America’s #1 solar provider. Despite the frequency show of his glamorous and amiable side among the public, one of his close friends secretly told me of his severity towards his five children. I was curious about the heart of the matter. His friend whispered that Elon did not hope to see his children playing videogames all day, so he assigned a series of questions with various difficulty levels as a big obstacle for children’s access to videogames, aiming to restrain them from being indulged in games. Elon set a rule: If his children can get the right answer of the first question, they would get access to the videogame with one hour. If they wish to play for another hour, they must continue to answer the second, however more difficult question correctly, and so on. Now, five children are dying to play the hottest videogame ‘Pokemon GO’ for at least three hours. They luckily defeat the previous two questions. However, this time, they are pacing up and down in that the third question is a bit hard.

Elon Musk wrote in the third question card: Here is a picture vividly depicting a similar principle applied by my SolarCity’s products, i.e. solar panel. In the premise of the battery’s constant voltage at the bottom, we suppose the wavelength of bulb light has a linear relationship with the current intensity through claybank wires. Given that the 590 nm bulb light usually generates nearly 30% of the maximum current intensity (MCI in short), and one of my friends wishes to purchase a blub with 50% of the MCI, which appropriate type of the bulb should I recommend him?

Note: The white tag in the picture indicates the number of photons generated by the blub light, while the grey tag indicates the wavelength of the bulb light. Both number of photons and wavelength of the bulb light increases from left to right.

Would you like to help his children to tackle this problem and win three play hours for ‘Pokemon GO’?


0 People tried to answer this question

The bulb with 370 nm light
The bulb with 450 nm light
The bulb with 130 nm light
The bulb with 240 nm light


History of edits
Edited BY: Anni Liu Edit Date: 2016-08-17 14:39:38
Edited BY: Anni Liu Edit Date: 2016-08-17 14:38:28
Edited BY: Anni Liu Edit Date: 2016-08-17 14:33:47
Edited BY: Anni Liu Edit Date: 2016-08-16 13:44:28
Edited BY: Anni Liu Edit Date: 2016-08-16 13:17:41
Edited BY: Anni Liu Edit Date: 2016-08-16 13:16:30