Magyar Information Contest Journal Articles

# Problem P. 4042. (January 2008)

P. 4042. A filament lamp rated at 40 W transforms 2% of the total energy to visible light. Suppose that the time of the emission of one photon is 10-14 second. Find the average number of visible photons emitted by the filament at the same time.

(4 pont)

Deadline expired on 11 February 2008.

### Statistics:

 85 students sent a solution. 4 points: 56 students. 3 points: 12 students. 2 points: 5 students. 1 point: 9 students. Unfair, not evaluated: 3 solutions.

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