Problem P. 4052. (February 2008)

P. 4052. The window of a room is covered by black paper. There is a square-shaped hole on the paper, through which the red light of the setting sun - nearly perpendicularly - is projected onto the opposite white wall. The distance between the wall and the window is 3.2 m. What is the size and the shape of the light spot on the wall if the area of the square is

a) 1 dm²;

b) 1 mm²;

c) 10^-10 m²?

(5 pont)

Deadline expired on March 11, 2008.

Statistics:

19 students sent a solution.
5 points:	Almási 270 Gábor András, Harsányi Szabolcs, Szolnoki Lénárd.
4 points:	Gulyás Máté, Győry Erika, Ölvedi Tibor.
3 points:	1 student.
2 points:	5 students.
1 point:	2 students.
0 point:	3 students.
Unfair, not evaluated:	2 solutionss.

Problems in Physics of KöMaL, February 2008