@ARTICLE {, title = {Vodné presýpacie hodiny}, author = {Baník, Rastislav}, journal = {Obzory matematiky, fyziky a informatiky}, year = {2004}, volume = {33}, number = {4}, pages = {50--53}, issn = {1335-4981}, abstract = {The Interesting Water Clock / Timer – The Water Minutes Counter In the teaching of physics are experiments very important, this is in general well known. The great role play there particularly motivational / incentive experiments. Many interesting experiments can be recommended for pupils as home experiments too. This article is devoted to the interesting time-measurement device, which can be built at home – using common stuff around an usual house. Such product should remember us the concise history of time-measurement and can contribute to better understanding of properties of liquids and gases. The time range may be here adjusted from some minutes to some hours, depending mainly on used volume of bottles and on applied liquid's properties. Such "water timer" is both edifying and interesting ... and it is surely funny also!}, }