{"id":2460,"date":"2026-02-13T23:04:22","date_gmt":"2026-02-13T21:04:22","guid":{"rendered":"https:\/\/science-x.net\/?page_id=2460"},"modified":"2026-02-13T23:04:23","modified_gmt":"2026-02-13T21:04:23","slug":"capacitor-calculator-c-q-v-energy-rc","status":"publish","type":"page","link":"https:\/\/science-x.net\/?page_id=2460","title":{"rendered":"Capacitor Calculator (C, Q, V, Energy, RC)"},"content":{"rendered":"\n<div class=\"eco-tool wp-block-group\" id=\"eco-tool-cap-0c41a\">\n  <div class=\"eco-tool__header\">\n    <h2 class=\"eco-tool__title\">Capacitor Calculator (C, Q, V, Energy, RC)<\/h2>\n    <p class=\"eco-tool__lead\">\n      Solve capacitor relationships (C = Q\/V) and compute stored energy (\u00bdCV\u00b2). Optionally compute RC time constant (\u03c4 = R\u00b7C).\n    <\/p>\n  <\/div>\n\n  <form class=\"eco-tool__form\" id=\"eco-cap-form-0c41a\" novalidate>\n    <div class=\"eco-tool__grid3\">\n      <!-- Unknown -->\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-cap-unknown-0c41a\">\n          Solve for<br>(unknown)\n        <\/label>\n        <select class=\"eco-tool__input\" id=\"eco-cap-unknown-0c41a\">\n          <option value=\"c\" selected>Capacitance (C)<\/option>\n          <option value=\"q\">Charge (Q)<\/option>\n          <option value=\"v\">Voltage (V)<\/option>\n        <\/select>\n        <div class=\"eco-tool__hint\">Enter the other two values.<\/div>\n      <\/div>\n\n      <!-- Capacitance -->\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-cap-c-0c41a\">\n          Capacitance (C)<br>(Farads, F)\n        <\/label>\n        <input class=\"eco-tool__input\" id=\"eco-cap-c-0c41a\" type=\"number\" step=\"any\" placeholder=\"e.g., 1e-6\" inputmode=\"decimal\" \/>\n        <div class=\"eco-tool__hint\">Examples: 1e-6 F = 1 \u00b5F, 1e-9 F = 1 nF.<\/div>\n      <\/div>\n\n      <!-- Charge -->\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-cap-q-0c41a\">\n          Charge (Q)<br>(Coulombs, C)\n        <\/label>\n        <input class=\"eco-tool__input\" id=\"eco-cap-q-0c41a\" type=\"number\" step=\"any\" placeholder=\"e.g., 2e-6\" inputmode=\"decimal\" \/>\n        <div class=\"eco-tool__hint\">Supports scientific notation (e.g., 2e-6).<\/div>\n      <\/div>\n\n      <!-- Voltage -->\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-cap-v-0c41a\">\n          Voltage (V)<br>(Volts, V)\n        <\/label>\n        <input class=\"eco-tool__input\" id=\"eco-cap-v-0c41a\" type=\"number\" step=\"any\" placeholder=\"e.g., 5\" inputmode=\"decimal\" \/>\n        <div class=\"eco-tool__hint\">Voltage across the capacitor.<\/div>\n      <\/div>\n\n      <!-- Resistance -->\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-cap-r-0c41a\">\n          Resistance (R)<br>(Ohms, \u03a9) optional\n        <\/label>\n        <input class=\"eco-tool__input\" id=\"eco-cap-r-0c41a\" type=\"number\" min=\"0\" step=\"any\" placeholder=\"e.g., 1000\" inputmode=\"decimal\" \/>\n        <div class=\"eco-tool__hint\">If provided, we compute \u03c4 = R\u00b7C.<\/div>\n      <\/div>\n\n      <!-- Formulas -->\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\">Formulas<\/label>\n        <div class=\"eco-tool__noteBox\">\n          C = Q \/ V<br>\n          Q = C \u00b7 V<br>\n          V = Q \/ C<br>\n          Energy: E = \u00bd C V\u00b2<br>\n          Time constant: \u03c4 = R \u00b7 C\n        <\/div>\n        <div class=\"eco-tool__hint\">Assumes ideal capacitor.<\/div>\n      <\/div>\n    <\/div>\n\n    <div class=\"eco-tool__actions\">\n      <button type=\"button\" class=\"wp-element-button eco-tool__btn\" id=\"eco-cap-calc-0c41a\">Calculate<\/button>\n      <button type=\"button\" class=\"wp-element-button eco-tool__btn eco-tool__btn--ghost\" id=\"eco-cap-reset-0c41a\">Reset<\/button>\n      <div class=\"eco-tool__error\" id=\"eco-cap-error-0c41a\" aria-live=\"polite\"><\/div>\n    <\/div>\n  <\/form>\n\n  <div class=\"eco-tool__result\" id=\"eco-cap-result-0c41a\" hidden>\n    <h3 class=\"eco-tool__subtitle\">Results<\/h3>\n\n    <div class=\"eco-tool__cards\">\n      <div class=\"eco-tool__card\">\n        <div class=\"eco-tool__metric-label\">Capacitance (C)<\/div>\n        <div class=\"eco-tool__metric-value\" id=\"eco-cap-out-c-0c41a\">\u2014<\/div>\n        <div class=\"eco-tool__metric-sub\">Farads (F)<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__card\">\n        <div class=\"eco-tool__metric-label\">Charge (Q)<\/div>\n        <div class=\"eco-tool__metric-value\" id=\"eco-cap-out-q-0c41a\">\u2014<\/div>\n        <div class=\"eco-tool__metric-sub\">Coulombs (C)<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__card\">\n        <div class=\"eco-tool__metric-label\">Voltage (V)<\/div>\n        <div class=\"eco-tool__metric-value\" id=\"eco-cap-out-v-0c41a\">\u2014<\/div>\n        <div class=\"eco-tool__metric-sub\">Volts (V)<\/div>\n      <\/div>\n    <\/div>\n\n    <div class=\"eco-tool__cards\" style=\"margin-top:10px;\">\n      <div class=\"eco-tool__card\">\n        <div class=\"eco-tool__metric-label\">Stored energy (E)<\/div>\n        <div class=\"eco-tool__metric-value\" id=\"eco-cap-out-e-0c41a\">\u2014<\/div>\n        <div class=\"eco-tool__metric-sub\">Joules (J)<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__card\">\n        <div class=\"eco-tool__metric-label\">RC time constant (\u03c4)<\/div>\n        <div class=\"eco-tool__metric-value\" id=\"eco-cap-out-tau-0c41a\">\u2014<\/div>\n        <div class=\"eco-tool__metric-sub\">seconds (if R provided)<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__card\">\n        <div class=\"eco-tool__metric-label\">Quick note<\/div>\n        <div class=\"eco-tool__metric-sub\" id=\"eco-cap-note-0c41a\">\u2014<\/div>\n      <\/div>\n    <\/div>\n\n    <div class=\"eco-tool__card eco-tool__card--wide\">\n      <div class=\"eco-tool__metric-label\">Equation summary<\/div>\n      <div class=\"eco-tool__metric-sub\" id=\"eco-cap-eq-0c41a\">\u2014<\/div>\n      <div class=\"eco-tool__metric-sub eco-tool__muted\">Supports scientific notation (e.g., 1e-6).<\/div>\n    <\/div>\n\n    <p class=\"eco-tool__note\">\n      For RC circuits, ~63% charging\/discharging happens in one time constant (\u03c4).\n    <\/p>\n  <\/div>\n<\/div>\n\n<style>\n.eco-tool{border:1px solid rgba(0,0,0,.12);border-radius:12px;padding:16px}\n.eco-tool__grid3{display:grid;grid-template-columns:1fr;gap:16px}\n@media 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Check inputs.\");\n      resEl.hidden=true; return;\n    }\n\n    \/\/ Energy: 1\/2 C V^2\n    const E = 0.5 * c * v * v;\n\n    \/\/ RC: tau = R*C if R provided and valid\n    const tau = (Number.isFinite(R) && R > 0) ? 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Optionally compute RC time constant (\u03c4 = R\u00b7C). Solve for(unknown) Capacitance (C)Charge&hellip;<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":2354,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_sitemap_exclude":false,"_sitemap_priority":"","_sitemap_frequency":"","footnotes":""},"_links":{"self":[{"href":"https:\/\/science-x.net\/index.php?rest_route=\/wp\/v2\/pages\/2460"}],"collection":[{"href":"https:\/\/science-x.net\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/science-x.net\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/science-x.net\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/science-x.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2460"}],"version-history":[{"count":1,"href":"https:\/\/science-x.net\/index.php?rest_route=\/wp\/v2\/pages\/2460\/revisions"}],"predecessor-version":[{"id":2461,"href":"https:\/\/science-x.net\/index.php?rest_route=\/wp\/v2\/pages\/2460\/revisions\/2461"}],"up":[{"embeddable":true,"href":"https:\/\/science-x.net\/index.php?rest_route=\/wp\/v2\/pages\/2354"}],"wp:attachment":[{"href":"https:\/\/science-x.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2460"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}