MIT Kraków https://validator.w3.org/feed/docs/rss2.html Muzeum Inżynierii i Techniki Sprocket wheel First-order lever Scientific gym Blocks Sand sculptures Draw on sand Excavator Lissajous Figures Sinusoid Sandy Planet Seesaw Double swing Single swing Rocket Supercool playground Beats Tubular bells Triangles The doppler effect Sound speed Wind gongs Tam-tam gong Xylophone Humming pipes Pipe organs Stone cimbalom Purring stone Acoustic telegraph Keyboard aerophone Focusing of sound Water in a rotating cylinder Water in a spinning sphere Joule’s experiment Hydraulic scale Water vortex The Bermuda triangle Cartesian diver Magnetic pendulum Hourglass Chaotic pendulum Magnet races Eddy currents Two mirrors Facial composition Giant kaleidoscope Distorting mirror Cylindrical mirror Periscope Crater