{"id":35,"date":"2005-06-30T09:17:00","date_gmt":"2005-06-30T07:17:00","guid":{"rendered":"https:\/\/kids.esa.int\/what_is_gravity\/"},"modified":"2026-10-08T00:23:19","modified_gmt":"2026-10-07T22:23:19","slug":"what_is_gravity","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/da\/what_is_gravity\/","title":{"rendered":"Hvad er tyngdekraften?"},"content":{"rendered":"
\n

Har du nogensinde undret dig over, hvorfor du altid lander med et bump, uanset hvor h\u00f8jt du springer? Det samme sp\u00f8rgsm\u00e5l stillede folk sig for 340 \u00e5r siden. Dengang opdagede en britisk videnskabsmand ved navn Isaac Newton tyngdekraften.<\/p>\n<\/div>\n

128125 Historien fort\u00e6ller, hvordan Isaac var i sin have, da et \u00e6ble faldt ned p\u00e5 hans hoved. Mens han gnubbede sit bl\u00e5 m\u00e6rke, begyndte han at undre sig over, hvorfor \u00e6blet havde ramt ham og ikke i stedet var fl\u00f8jet opad.<\/p>\n

Newton kom frem til, at en usynlig kraft m\u00e5tte tr\u00e6kke \u00e6blet mod Jorden. Han kaldte denne kraft for \u201ctyngdekraften\u201d \u2013 fra det latinske ord \u201cgravitas\u201d, der betyder \u201cv\u00e6gt\u201d.<\/p>\n

\"Newton's
Newtons kanon<\/figcaption><\/figure>\n

Newton inds\u00e5, at ethvert objekt i universet tiltr\u00e6kker alle andre objekter i universet. Selv et \u00e6ble ud\u00f8ver en svag tiltr\u00e6kningskraft p\u00e5 alt omkring sig.<\/p>\n

Det er tyngdekraften, der holder M\u00e5nen i kredsl\u00f8b om Jorden, og det er tyngdekraften, der g\u00f8r det muligt for Solen at holde fast p\u00e5 sin familie af planeter. Solens og M\u00e5nens tiltr\u00e6kningskraft for\u00e5rsager ogs\u00e5 tidevandet i Jordens hav.<\/p>\n

Tyngdekraftens styrke afh\u00e6nger imidlertid af et objekts st\u00f8rrelse og t\u00e6thed \u2013 det, som forskerne kalder dets \u201cmasse\u201d. Det lille \u00e6bles tyngdekraft er for svag til at modst\u00e5 den enorme Jordens tiltr\u00e6kning, s\u00e5 det falder mod planetens centrum.<\/p>\n

Et objekts tyngdekraft aftager med afstanden fra det. En bjergbestiger p\u00e5 toppen af Mount Everest vejer lidt mindre end ved havoverfladen. Hvis et rumskib bev\u00e6ger sig langt nok v\u00e6k fra Jorden, vil det til sidst helt undslippe planetens tyngdekraft.<\/p>","protected":false},"excerpt":{"rendered":"

Have you ever wondered why you always fall back to the ground with a bump, no matter how high you jump? People were asking the same question 340 years ago. […]<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"esa_banner_image":"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2002\/01\/sir_isaac_newton_1642-17272\/17864713-3-eng-GB\/Sir_Isaac_Newton_1642-1727.jpg","esa_banner_description":"Sir Isaac Newton, 1642-1727","esa_banner_credit":"Isaac Newton Institute for Mathematical Studies","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2002\/01\/Sir_Isaac_Newton_1642-17272","esa_external_url":"","esa_external_new_window":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":true},"categories":[10,11,19],"tags":[2],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-35","post","type-post","status-publish","format-standard","hentry","category-learn","category-our-universe","category-story-of-the-universe","tag-background-article"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts\/35","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/comments?post=35"}],"version-history":[{"count":4,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts\/35\/revisions"}],"predecessor-version":[{"id":4271,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts\/35\/revisions\/4271"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/media?parent=35"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/categories?post=35"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/tags?post=35"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/panel?post=35"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/language?post=35"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/age?post=35"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/duration?post=35"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/resource_type?post=35"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/audience?post=35"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/wf_post_folders?post=35"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}