**P. 4486.** Sam was courious to find the speed of the elevator in their house. For his measurement he used a bathroom scale and a stopwatch. He got into the lift at the groundfloor, stood on the the scale and recorded the readings on the scale. The reading was 50 kg when the elevator was at rest, and for 2 seconds right after the lift started to move the reading of the scale was 52 kg. What is the speed of the elevator when it moves uniformly?

(3 points)

**Deadline expired on 10 January 2013.**