{"product_id":"hertzs-spark-plate-018-physics-poster","title":"Hertz's Spark – Plate 018 Physics Poster","description":"\u003cp\u003ePlate 18 speaks for itself: \u003cem\u003e“Light, without the light.”\u003c\/em\u003e\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eHertz made sparks in one circuit and detected sparks in a separate loop across the room, showing that electromagnetic waves exist and travel like light, as Maxwell predicted.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003ec = 1 \/ √(μ₀ ε₀)\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003ec: speed of light in vacuum, m s⁻¹\u003c\/li\u003e\n\u003cli\u003eμ₀: vacuum permeability, N A⁻²\u003c\/li\u003e\n\u003cli\u003eε₀: vacuum permittivity, F m⁻¹\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003ec = 299 792 458 m\/s (exact). Karlsruhe, 1886–88.\u003c\/p\u003e\u003ch3\u003eSources\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eH. Hertz, Ann. Phys. 270, 551 (1888).\u003c\/li\u003e\n\u003cli\u003eSI Brochure, 9th ed. (2019): exact c.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOn the poster\u003c\/h3\u003e\u003cp\u003ePlate 018, “Hertz's Spark”: the pixel-art plate with its slogan “Light, without the light.”, 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":50961788698727,"sku":"17054142304611237263","price":19.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Fine Art","offer_id":50961788731495,"sku":"25338062954947956419","price":29.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Semi Glossy","offer_id":50961788764263,"sku":"12818708698648184742","price":19.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Fine Art","offer_id":50961788797031,"sku":"45816744372068679907","price":44.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Semi Glossy","offer_id":50961788829799,"sku":"10234489483603219685","price":29.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Matte","offer_id":50961788862567,"sku":"21569538999694879345","price":29.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Matte","offer_id":50961788895335,"sku":"81812656330102197884","price":69.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Fine Art","offer_id":50961788928103,"sku":"28434235702535068756","price":119.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Semi Glossy","offer_id":50961788960871,"sku":"19453216303361765152","price":69.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/3944712174035221566_2048.jpg?v=1793731099","url":"https:\/\/pixelatedphysics.com\/sv\/products\/hertzs-spark-plate-018-physics-poster","provider":"Pixelated Physics","version":"1.0","type":"link"}