Physicsfun - Undial Sundial
Sympa comme gadget: l'heure solaire par ombre portée
Undial Sundial: modern design of an ancient timekeeping device where a slanted stick (the gnomon) casts a shadow to indicate the time (this one designed for 30-40 degrees latitude).
La vidéo:
This novel design has no dial underneath, instead the hours are laser etched into clear acrylic such that the time appears projected within the cast shadow. 10 AM to 3:00 PM of a sunny day in Fresno are shown here in time-lapse. Note the movement of the shadow cast by the sun as the Earth turns underneath during this five hour period. Perfect for a windowsill that gets noonday sun! ➡️ Follow the link in my profile for info on where to buy this sundial and other amazing items featured here on @physicsfun