Vísindavefurinn

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src="/design/i_vv/icon-neurology.svg" alt=""> <span style="color:#00457C"> Vísindavefur </span> <img class="arrow-icon" src="/design/i_vv/arrow_right.svg"> </a> </li> <li class="cat-teal"> <a href="/vegna_thess.php?id=202"> <img src="/design/i_vv/icon-account-balance.svg" alt=""> <span style="color:#00457C"> Þverfræðilegt efni </span> <img class="arrow-icon" src="/design/i_vv/arrow_right.svg"> </a> </li> </ul> </nav> <div class="header-desktop"> <nav class="desktop-nav" role="navigation"> <ul> <li><a href="/svar.php?id=73555">Tölfræði</a></li> <li><a href="/svar.php?id=70789">Um vefinn</a></li> <li><a href="/svar.php?id=70790">Þjónusta</a></li> <li class="search"> <form class="searchbar" action="/search/" method="GET"> <input type="search" name="q" class="d-search" placeholder="Sláðu inn leitarorð og ýttu á „enter“" /> <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none"> <mask id="mask0_853_7542" style="mask-type:alpha" 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class="search-button btn btn-light"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-search"><circle cx="11" cy="11" r="8"></circle><line x1="21" y1="21" x2="16.65" y2="16.65"></line></svg></a> <div class="header-question"> <a href="/hvers_vegna.php?id=" onclick="javascript:$('a.send-question').click(); return false;" class="btn send">Senda inn spurningu <img src="/design/i_vv/message.svg" alt="message icon"></a> </div> </nav> <div class="header-data"> <div class="data-item"> <img src="/design/i_vv/icon-sun.svg" alt="Sólin"> Sólin <strong>Rís 10:46 • sest 15:47</strong> <span>í Reykjavík</span> </div> <div class="data-item"> <img src="/design/i_vv/icon-moon.svg" alt="Tunglið"> Tunglið <strong>Rís 00:00 • Sest 00:00</strong> <span>í Reykjavík</span> </div> <div class="data-item"> <img src="/design/i_vv/icon-flood.svg" alt="Flóð"> Flóð <strong>Árdegis: 06:20 • Síðdegis: 18:33</strong> <span>í Reykjavík</span> </div> <div class="data-item"> <img src="/design/i_vv/icon-tide.svg" alt="Fjaran"> Fjara <strong>Árdegis: 00:05 • Síðdegis: 12:35</strong> <span>í Reykjavík</span> </div> </div> </div> </div> <div class="header-data"> <div class="data-item"> <img src="/design/i_vv/icon-sun.svg" alt="Sólin"> Sólin <strong>Rís 10:46 • sest 15:47</strong> <span>í Reykjavík</span> </div> <div class="data-item"> <img src="/design/i_vv/icon-moon.svg" alt="Tunglið"> Tunglið <strong>Rís 00:00 • Sest 00:00</strong> <span>í Reykjavík</span> </div> <div class="data-item"> <img src="/design/i_vv/icon-flood.svg" alt="Flóð"> Flóð <strong>Árdegis: 06:20 • Síðdegis: 18:33</strong> <span>í Reykjavík</span> </div> <div class="data-item"> <img src="/design/i_vv/icon-tide.svg" alt="Fjaran"> Fjara <strong>Árdegis: 00:05 • Síðdegis: 12:35</strong> <span>í Reykjavík</span> </div> </div> </header> <div class="poppin md-send"> <a class="instructions" href="#">Leiðbeiningar<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-help-circle"><circle cx="12" cy="12" r="10"></circle><path d="M9.09 9a3 3 0 0 1 5.83 1c0 2-3 3-3 3"></path><line x1="12" y1="17" x2="12.01" y2="17"></line></svg></a><a class="instructions-close" href="#">Til baka <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-arrow-left"><line x1="19" y1="12" x2="5" y2="12"></line><polyline points="12 19 5 12 12 5"></polyline></svg></a> <h2>Sendu inn spurningu </h2> <div class="instructions-more"> <p class="first">Hér getur þú sent okkur nýjar spurningar um vísindaleg efni.</p> <p>Hafðu spurninguna stutta og hnitmiðaða og sendu aðeins eina í einu. Einlægar og vandaðar spurningar um mikilvæg efni eru líklegastar til að kalla fram vönduð og greið svör. Ekki er víst að tími vinnist til að svara öllum spurningum.</p> <p>Persónulegar upplýsingar um spyrjendur eru eingöngu notaðar í starfsemi vefsins, til dæmis til að svör verði við hæfi spyrjenda. Spurningum er ekki sinnt ef spyrjandi villir á sér heimildir eða segir ekki nægileg deili á sér.</p> <p>Spurningum sem eru ekki á verksviði vefsins er eytt.</p> <p>Að öðru leyti er hægt að spyrja Vísindavefinn um allt milli himins og jarðar!</p> <div class="content-left-sep"></div> </div> <form action="/hvers_vegna.php?id=" method="POST" name="question_send"> <div class="md-fields"> <input type="hidden" name="step" value="4"> <div class="md-input"> <label for="s-fname">Nafn</label> <input type="text" name="f_name" class="send-input" id="s-fname" required="required" value=""> <input type="hidden" name="l_name" class="send-input" id="s-sname" value=""> </div> <div class="md-input"> <label for="s-email">Netfang</label> <input type="email" name="email" class="send-input" id="s-email" required="required" value=""> </div> <div class="md-input"> <label for="s-byear">Fæðingarár</label> <input type="number" name="birthyear" class="send-input" id="s-byear" maxlength="4" required="required" value=""> </div> <div class="md-input"> <label for="s-math">Ruslpóstvörn</label> <input type="hidden" name="vv_math_problem_hash_id" class="vv_math_problem_hash_id" id="vv_math_problem_hash_id" value=""> <input type="text" name="vv_math_problem_answer" id="vv_math_problem_answer" class="send-input" valuesize="2" maxlength="2" required="required" style="width: 30%;"> <span class="s-math-container"> = <span class="math_problem_num1_txt"></span> <img class="math_problem_math_icon" src="" /> <span class="math_problem_num2_txt"></span> </span> </div> <div class="md-input"> <label for="s-question">Spurning</label> <textarea type="text" name="question" class="send-input i-question" id="s-question" rows="6" required="required"></textarea> </div> </div> <div class="md-actions"> <button type="button" value="" class="btn btn-white"><i data-feather="x"></i> Hætta við</button> <button type="submit" value="Senda" class="btn send-button"><i data-feather="check"></i> Senda</button> </div> </form> </div> <section class="layout"> <div class="main-content"> <div class="backdrop-blue"> <div class="category-title article-header layout-item"> <div class="breadcrumbs-button"> <img class="br-arrow" src="/design/i_vv/icon-arrow-left.svg"> <img class="br-home" src="/design/i_vv/icon-home.svg"> <a class="br-back" href="/">Forsíða</a> <span>Flokkar</span> </div> <div class="headlines-elements"> <h1 class="page-title">Flokkar</h1> <p>Hér getur þú skoðað svörin á vefnum eftir efnisflokkum.</p><p>Ef þú smellir á "Allir flokkar" getur þú séð öll svörin í öfugri tímaröð þannig að nýjustu svörin koma fyrst. Þú getur einnig skoðað <a href="/vegna_thess.php?id=138">lista yfir nýleg svör</a></p> </div> </div> </div> <div class="categories-list layout-item"> <ul class="categories"> <li><a href="/vegna_thess.php?id=138">Allir flokkar</a></li> <li><a href="/vegna_thess.php?id=93">Bekkirnir spyrja</a></li> <li><a href="/vegna_thess.php?id=50">Bókmenntir og listir</a></li> <li><a href="/flokkur/249/covid-19-upplyst-umraeda/">COVID-19 — upplýst umræða</a></li> <li><a href="/vegna_thess.php?id=140">Dagatal vísindamanna</a></li> <li><a href="/flokkur/242/dagatal-islenskra-visindamanna/">Dagatal íslenskra vísindamanna</a></li> <li><a href="/vegna_thess.php?id=6">Efnafræði</a></li> <li><a href="/vegna_thess.php?id=4">Eðlisfræði: fræðileg</a></li> <li><a href="/vegna_thess.php?id=64">Eðlisfræði: í daglegu lífi</a></li> <li><a href="/vegna_thess.php?id=88">Fornfræði</a></li> <li><a href="/vegna_thess.php?id=89">Fornleifafræði</a></li> <li><a href="/vegna_thess.php?id=54">Félagsvísindi almennt</a></li> <li><a href="/vegna_thess.php?id=69">Föstudagssvar</a></li> <li><a href="/vegna_thess.php?id=76">Gátur og heilabrot</a></li> <li><a href="/vegna_thess.php?id=15">Hagfræði</a></li> <li><a href="/vegna_thess.php?id=21">Heimspeki</a></li> <li><a href="/vegna_thess.php?id=120">Íþróttafræði</a></li> <li><a href="/vegna_thess.php?id=19">Jarðvísindi</a></li> <li><a href="/vegna_thess.php?id=199">Kynfræði</a></li> <li><a href="/flokkur/247/kynjafraedi/">Kynjafræði</a></li> <li><a href="/vegna_thess.php?id=61">Landafræði</a></li> <li><a href="/vegna_thess.php?id=17">Læknisfræði</a></li> <li><a href="/vegna_thess.php?id=8">Lífvísindi: almennt</a></li> <li><a href="/vegna_thess.php?id=65">Lífvísindi: dýrafræði</a></li> <li><a href="/vegna_thess.php?id=63">Lífvísindi: mannslíkaminn</a></li> <li><a href="/vegna_thess.php?id=37">Lögfræði</a></li> <li><a href="/vegna_thess.php?id=72">Mannfræði</a></li> <li><a href="/vegna_thess.php?id=153">Menntunarfræði</a></li> <li><a href="/flokkur/239/mid-austurlond/">Mið-Austurlönd</a></li> <li><a href="/vegna_thess.php?id=205">Myndbönd</a></li> <li><a href="/vegna_thess.php?id=225">Málstofa</a></li> <li><a href="/vegna_thess.php?id=80">Málvísindi: almennt</a></li> <li><a href="/vegna_thess.php?id=28">Málvísindi: íslensk</a></li> <li><a href="/vegna_thess.php?id=39">Næringarfræði</a></li> <li><a href="/vegna_thess.php?id=83">Orkumál</a></li> <li><a href="/vegna_thess.php?id=81">Sagnfræði: mannkynssaga</a></li> <li><a href="/vegna_thess.php?id=20">Sagnfræði: Íslandssaga</a></li> <li><a href="/flokkur/240/stadreynda-_og_samfelagsvakt">Staðreynda- og samfélagsvakt</a></li> <li><a href="/vegna_thess.php?id=78">Stjarnvísindi: alheimurinn</a></li> <li><a href="/vegna_thess.php?id=9">Stjarnvísindi: almennt</a></li> <li><a href="/vegna_thess.php?id=77">Stjarnvísindi: sólkerfið</a></li> <li><a href="/flokkur/250/stjornarskra/">Stjórnarskrá</a></li> <li><a href="/vegna_thess.php?id=62">Stjórnmálafræði</a></li> <li><a href="/vegna_thess.php?id=5">Stærðfræði</a></li> <li><a href="/vegna_thess.php?id=14">Sálfræði</a></li> <li><a href="/vegna_thess.php?id=52">Trúarbrögð</a></li> <li><a href="/vegna_thess.php?id=16">Tölvunarfræði</a></li> <li><a href="/vegna_thess.php?id=79">Umhverfismál</a></li> <li><a href="/vegna_thess.php?id=66">Unga fólkið svarar</a></li> <li><a href="/flokkur/248/veirur-og-covid-19/">Veirur og COVID-19</a></li> <li><a href="/vegna_thess.php?id=53">Verkfræði og tækni</a></li> <li><a href="/vegna_thess.php?id=35">Veðurfræði</a></li> <li><a href="/flokkur/238/visindafraedi/">Vísindafræði</a></li> <li><a href="/vegna_thess.php?id=223">Vísindafréttir</a></li> <li><a href="/vegna_thess.php?id=151">Vísindasaga</a></li> <li><a href="/vegna_thess.php?id=214">Vísindasmiðjan</a></li> <li><a href="/vegna_thess.php?id=118">Vísindavefurinn</a></li> <li><a href="/vegna_thess.php?id=32">Vísindi almennt</a></li> <li><a href="/vegna_thess.php?id=90">Þjóðfræði</a></li> <li><a href="/vegna_thess.php?id=202">Þverfræðilegt efni</a></li> <li><a href="/flokkur/258/ornefni/">örnefni</a></li> <li><a href="/flokkur/241/1918/">1918</a></li> <li><a href="/flokkur/246/1944/">1944</a></li> </ul> </div> </div> </section> <footer> <section> <div class="footer-container"> <div class="footer-left-right"> <div class="footer-left"> <a href="/"><div class="logo-bottom"></div></a> </div> <div class="footer-center contact-info">  <ul class="contact-list">  <li><img src="/design/i_vv/icon-location.svg" alt="">Dunhaga 5, 107 Reykjavík</li> <li><img src="/design/i_vv/icon-telephone.svg" alt=""><a href="tel:+3545254765">525-4765</a></li> <li class="f-email"><img src="/design/i_vv/icon-email.svg" alt=""><a href="mailto:visindavefur@hi.is">Tölvupóstur <span class="extra">til ritstjórnar</span></a></li>  </ul>  </div> <div class="footer-right"> <a href="#" class="arrow-btn scroll-up">Skruna upp<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" 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