{"product_id":"orsteds-needle-plate-016-physics-poster","title":"Ørsted's Needle – Plate 016 Physics Poster","description":"\u003cp\u003ePlate 16 speaks for itself: \u003cem\u003e“The needle turned, and two forces became one.”\u003c\/em\u003e\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eØrsted saw a compass needle swing when current ran through a nearby wire: electric currents make magnetic fields. The field circles a long straight wire and falls off as 1\/r.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eB = μ₀ I \/ (2π r)\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eB: magnetic flux density, T\u003c\/li\u003e\n\u003cli\u003eμ₀: vacuum permeability ≈ 1.25664×10⁻⁶ N A⁻²\u003c\/li\u003e\n\u003cli\u003eI: current, A\u003c\/li\u003e\n\u003cli\u003er: distance from the wire, m\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eA current turns a compass. Copenhagen, 21 July 1820.\u003c\/p\u003e\u003ch3\u003eSources\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eH. C. Ørsted, Experimenta circa effectum conflictus electrici in acum magneticam (21 July 1820).\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eOn the poster\u003c\/h3\u003e\u003cp\u003ePlate 016, “Ørsted's Needle”: the pixel-art plate with its slogan “The needle turned, and two forces became one.”, 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":50961748656231,"sku":"87297615033635848605","price":19.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Fine Art","offer_id":50961748688999,"sku":"17662267056740814481","price":29.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Semi Glossy","offer_id":50961748721767,"sku":"25688546468290228485","price":19.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Fine Art","offer_id":50961748754535,"sku":"16176231748110202371","price":44.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Semi Glossy","offer_id":50961748787303,"sku":"20869512887859499597","price":29.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Matte","offer_id":50961748820071,"sku":"12869024059295772470","price":29.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Matte","offer_id":50961748852839,"sku":"31990266961363358512","price":69.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Fine Art","offer_id":50961748885607,"sku":"14303581202989378885","price":119.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Semi Glossy","offer_id":50961748918375,"sku":"16066521357955375740","price":69.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/5102066307106232197_2048.jpg?v=1793731035","url":"https:\/\/pixelatedphysics.com\/sv\/products\/orsteds-needle-plate-016-physics-poster","provider":"Pixelated Physics","version":"1.0","type":"link"}