{"product_id":"corpuscle-jj-thomson","title":"Corpuscle – J. J. Thomson and the Electron \/ m\/e ≪ H Ion Physics Sticker","description":"\u003cp\u003eCorpuscle, a dark-haired experimenter, leans beside a glass tube carrying a straight green beam.\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eIn 1897 J. J. Thomson crossed electric and magnetic fields over a cathode-ray beam (“Cathode Rays”, Phil. Mag. 44, 293). He tuned them so the beam ran straight, which gives its speed, v = E\/B; then the deflection from one field alone gives the mass-to-charge ratio. The result was about a thousand times smaller than for the hydrogen ion, whatever the gas or electrode metal. He called the particles corpuscles: we call them electrons.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003ev = E\/B\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003ev: beam speed (m\/s)\u003c\/li\u003e\n\u003cli\u003eE: electric field (V\/m)\u003c\/li\u003e\n\u003cli\u003eB: magnetic field (T)\u003c\/li\u003e\n\u003cli\u003em\/e: mass-to-charge ratio of the particle (kg\/C)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eThomson measured only the ratio. The charge itself came from Millikan's oil-drop work (1909–13); modern values give an electron about 1\/1836 of the hydrogen ion's mass.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eHonest caveat:\u003c\/em\u003e His 1897 ratio was rough (about 1\/1000 rather than 1\/1836), and others including Wiechert and Kaufmann measured similar ratios that year.\u003c\/p\u003e\u003ch3\u003eOn the sticker\u003c\/h3\u003e\u003cp\u003eCorpuscle sits beside a glass discharge tube with a straight glowing green beam. Printed text: \u003cstrong\u003eCORPUSCLE\u003c\/strong\u003e with the line \u003cstrong\u003em\/e \u0026lt;\u0026lt; H ION\u003c\/strong\u003e. Pixel-art kiss-cut vinyl sticker, white, in 2″, 3″, 4″ and 6″ sizes.\u003c\/p\u003e","brand":"Printify","offers":[{"title":"2\" × 2\" \/ White","offer_id":50964061880423,"sku":"24561959220433089122","price":4.99,"currency_code":"USD","in_stock":true},{"title":"3\" × 3\" \/ White","offer_id":50964061913191,"sku":"21807753413080401223","price":6.99,"currency_code":"USD","in_stock":true},{"title":"4\" × 4\" \/ White","offer_id":50964061945959,"sku":"10883977214102412067","price":8.99,"currency_code":"USD","in_stock":true},{"title":"6\" × 6\" \/ White","offer_id":50964061978727,"sku":"14804440710640428511","price":11.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/2197347303040983049_1200.jpg?v=1793659078","url":"https:\/\/pixelatedphysics.com\/tr\/products\/corpuscle-jj-thomson","provider":"Pixelated Physics","version":"1.0","type":"link"}