{"product_id":"pitota-pitot-tube","title":"Pitota – The Pitot Tube \/ h = v²\/(2g) Physics Sticker","description":"\u003cp\u003ePitota, a tricorn-hatted river engineer, studies water rising in a glass tube.\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eIn 1732 Henri Pitot reported to the Paris Academy a bent glass tube he had dipped into the Seine with its mouth facing the current. The water in it stood higher than the river surface, and the extra height measured the flow speed. Bringing the moving water to rest at the mouth turns its kinetic energy into pressure head. He found water near the surface flowing faster than deeper down, overturning the belief of the day.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eh = v²\/(2g)\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eh: rise of water in the tube above the free surface (m)\u003c\/li\u003e\n\u003cli\u003ev: flow speed (m\/s)\u003c\/li\u003e\n\u003cli\u003eg: gravitational acceleration, 9.81 m\/s²\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eDouble the speed and the rise is four times as large. Aircraft airspeed indicators still use Pitot tubes, with a static port.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eHonest caveat:\u003c\/em\u003e The formula is ideal: it ignores viscosity, turbulence and probe shape, and in compressible flows near the speed of sound it needs corrections.\u003c\/p\u003e\u003ch3\u003eOn the sticker\u003c\/h3\u003e\u003cp\u003ePitota holds a glass vessel and tube of glowing blue water, with a river behind him. Printed text: \u003cstrong\u003ePITOTA\u003c\/strong\u003e with the line \u003cstrong\u003eh = v²\/(2g)\u003c\/strong\u003e. Pixel-art kiss-cut vinyl sticker, white, in 2″, 3″, 4″ and 6″ sizes.\u003c\/p\u003e","brand":"Pixelated Physics","offers":[{"title":"2\" × 2\" \/ White","offer_id":50964056670311,"sku":"11859079448876911413","price":4.99,"currency_code":"USD","in_stock":true},{"title":"3\" × 3\" \/ White","offer_id":50964056703079,"sku":"22038589905960319607","price":6.99,"currency_code":"USD","in_stock":true},{"title":"4\" × 4\" \/ White","offer_id":50964056735847,"sku":"24947559578284499840","price":8.99,"currency_code":"USD","in_stock":true},{"title":"6\" × 6\" \/ White","offer_id":50964056768615,"sku":"99973802318021412785","price":11.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/5708723324393355695_1200.jpg?v=1793658964","url":"https:\/\/pixelatedphysics.com\/ja\/products\/pitota-pitot-tube","provider":"Pixelated Physics","version":"1.0","type":"link"}