Rain

https://www.youtube.com/watch?v=3MqYE2UuN24

The question in topic is taken from everyday life. Getting completely soaked in the rain is the situation which everyone has gone through at least once in his life. During this unpleasant time we often ask ourselves if is it better to run or to walk. This problem is explained in the video and the answer to this is not that obvious as it may seem and I think that not many people got it correct at first. I very much like the scientific way how the problem was explained, also pictures and animations used in this video were clear and helped to understand what author wanted to show.

parallelepiped (3D parallelogram)
parallelogram has 2 pairs of parallel sides which has the same length

slant
The needle must be slanted to fit properly