Mathematical and Physical Journal
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Problem P. 4096. (October 2008)

P. 4096. An object is 20 cm away from a concave mirror, and it is within the focal length of the mirror. If the mirror is changed to a plane mirror the image moves 15 cm closer to the mirror.

a) What is the focal length of the concave mirror?

b) Calculate the enlargement.

(3 pont)

Deadline expired on November 11, 2008.


161 students sent a solution.
3 points:81 students.
2 points:68 students.
1 point:9 students.
0 point:3 students.

Problems in Physics of KöMaL, October 2008