# Problem P. 4268. (September 2010)

**P. 4268.** A physics teacher often went to skate to a nearby frozen lake. Once he could reduce his speed to one third of its original value along 16 m skidding, and then it took him 1 more second to stop. How much distance did he cover during the braking. On another day he had the same initial speed and suddenly he noticed a crevasse in the ice 20 m in front of him. At what distance from the crevasse could he stop, if his reaction time is 0.1 s, and he used his familiar braking technique.

(4 pont)

**Deadline expired on October 11, 2010.**

Sorry, the solution is available only in Hungarian. Google translation

**Megoldás. ** A teljes fékezés során 18 métert tett meg. A másik esetben a rianástól 80 cm-re tudott megállni.

### Statistics:

285 students sent a solution. 4 points: 200 students. 3 points: 30 students. 2 points: 14 students. 1 point: 4 students. 0 point: 30 students. Unfair, not evaluated: 7 solutions.

Problems in Physics of KöMaL, September 2010