{"product_id":"the-thinning-sky-plate-091-physics-poster","title":"The Thinning Sky – Plate 091 Physics Poster","description":"\u003cp\u003ePlate 91 speaks for itself: \u003cem\u003e“At Everest, a third of the air remains.”\u003c\/em\u003e\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eAir pressure falls with height as the weight of the air above shrinks. The International Standard Atmosphere puts the summit of Everest at about 31 kPa, under a third of sea level.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003ep = p₀ (1 − L h \/ T₀)^(g M \/ R L)\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003ep: pressure at height h, Pa\u003c\/li\u003e\n\u003cli\u003ep₀: sea-level pressure 101 325 Pa\u003c\/li\u003e\n\u003cli\u003eL: lapse rate 0.0065 K m⁻¹\u003c\/li\u003e\n\u003cli\u003eh: altitude, m\u003c\/li\u003e\n\u003cli\u003eT₀: sea-level temperature 288.15 K\u003c\/li\u003e\n\u003cli\u003eg: 9.80665 m s⁻²\u003c\/li\u003e\n\u003cli\u003eM: molar mass of air 0.0289644 kg mol⁻¹\u003c\/li\u003e\n\u003cli\u003eR: gas constant 8.314 J mol⁻¹ K⁻¹\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAt 8849 m the ISA gives ≈ 31.4 kPa. That is a model value; real pressure varies.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eHonest caveat:\u003c\/em\u003e Measured summit pressure is usually somewhat higher, about 33–34 kPa, because the tropical air column is warmer.\u003c\/p\u003e\u003ch3\u003eSources\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eISO 2533:1975, Standard Atmosphere.\u003c\/li\u003e\n\u003cli\u003eJ. B. West, J. Appl. Physiol. 86, 1062 (1999).\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOn the poster\u003c\/h3\u003e\u003cp\u003ePlate 091, “The Thinning Sky”: the pixel-art plate with its slogan “At Everest, a third of the air remains.”, the key equation and the facts panel shown above. Pixelated Physics. Physics. Personified.\u003c\/p\u003e","brand":"Printify","offers":[{"title":"9'' x 12\" (Vertical) \/ Matte","offer_id":50962700664935,"sku":"11229701266694450875","price":19.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Fine Art","offer_id":50962700697703,"sku":"63971407409418761341","price":29.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Semi Glossy","offer_id":50962700730471,"sku":"13790132465836860771","price":19.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Fine Art","offer_id":50962700763239,"sku":"59841618863338648242","price":44.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Semi Glossy","offer_id":50962700796007,"sku":"28076470065019169529","price":29.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Matte","offer_id":50962700828775,"sku":"29080494851750700309","price":29.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Matte","offer_id":50962700861543,"sku":"15310219915710446557","price":69.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Fine Art","offer_id":50962700894311,"sku":"67795247702108382686","price":119.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Semi Glossy","offer_id":50962700927079,"sku":"76516339701404254253","price":69.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/12766244352619319230_2048.jpg?v=1793637855","url":"https:\/\/pixelatedphysics.com\/id\/products\/the-thinning-sky-plate-091-physics-poster","provider":"Pixelated Physics","version":"1.0","type":"link"}