{"id":611,"date":"2025-08-06T15:14:31","date_gmt":"2025-08-06T15:14:31","guid":{"rendered":"https:\/\/giapsgk.com\/chuyen-de\/?page_id=611"},"modified":"2025-08-06T15:14:50","modified_gmt":"2025-08-06T15:14:50","slug":"y-nghia-cua-cac-dai-luong-trong-vat-li","status":"publish","type":"page","link":"https:\/\/giapsgk.com\/chuyen-de\/dao-dong\/dao-dong-dieu-hoa\/y-nghia-cua-cac-dai-luong-trong-vat-li\/","title":{"rendered":"\u00dd ngh\u0129a c\u1ee7a c\u00e1c \u0111\u1ea1i l\u01b0\u1ee3ng trong v\u1eadt l\u00ed"},"content":{"rendered":"<p><strong>V\u00ed d\u1ee5 1: <\/strong>Ph\u01b0\u01a1ng tr\u00ecnh dao \u0111\u1ed9ng c\u00f3 d\u1ea1ng x = 2cos(2\u03c0t) trong \u0111\u00f3 x t\u00ednh b\u1eb1ng cm v\u00e0 t t\u00ednh b\u1eb1ng gi\u00e2y. G\u1ed1c th\u1eddi gian l\u00e0 l\u00fac v\u1eadt<\/p>\n<p>A. v\u1eadt \u0111ang \u1edf bi\u00ean \u0111\u1ed9 d\u01b0\u01a1ng.<\/p>\n<p>B. v\u1eadt \u0111ang \u1edf bi\u00ean \u0111\u1ed9 \u00e2m.<\/p>\n<p>C. v\u1eadt \u0111ang \u1edf VTCB chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u d\u01b0\u01a1ng.<\/p>\n<p>D. v\u1eadt \u0111ang \u1edf VTCB chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u \u00e2m.<\/p>\n<p style=\"text-align: center;\"><strong>Gi\u1ea3i<\/strong><\/p>\n<p>$t=0\\to \\left\\{ \\begin{align} &amp; x=2\\cos (2\\pi .0)=A \\\\ &amp; v=-4\\pi \\sin (2\\pi .0)=0 \\\\ \\end{align} \\right.\\,$<\/p>\n<p>Ch\u1ecdn A.<\/p>\n<p><strong>V\u00ed d\u1ee5 2: <\/strong>Ph\u01b0\u01a1ng tr\u00ecnh dao \u0111\u1ed9ng c\u00f3 d\u1ea1ng x = 10cos(\u03c0t &#8211; \u03c0\/2) trong \u0111\u00f3 x t\u00ednh b\u1eb1ng cm v\u00e0 t t\u00ednh b\u1eb1ng gi\u00e2y. G\u1ed1c th\u1eddi gian l\u00e0 l\u00fac v\u1eadt<\/p>\n<p>A. v\u1eadt \u0111ang \u1edf bi\u00ean \u0111\u1ed9 d\u01b0\u01a1ng.<\/p>\n<p>B. v\u1eadt \u0111ang \u1edf bi\u00ean \u0111\u1ed9 \u00e2m.<\/p>\n<p>C. v\u1eadt \u0111ang \u1edf VTCB chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u d\u01b0\u01a1ng.<\/p>\n<p>D. v\u1eadt \u0111ang \u1edf VTCB chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u \u00e2m.<\/p>\n<p style=\"text-align: center;\"><strong>Gi\u1ea3i<\/strong><\/p>\n<p>$t=0\\to \\left\\{ \\begin{align} &amp; x=10\\cos (\\pi .0-\\frac{\\pi }{2})=0 \\\\ &amp; v=-10\\pi \\sin (\\pi .0-\\frac{\\pi }{2})=A\\omega &gt;0 \\\\ \\end{align} \\right.\\,$<\/p>\n<p>Ch\u1ecdn C.<\/p>\n<p><strong>V\u00ed d\u1ee5 3: <\/strong>Ph\u01b0\u01a1ng tr\u00ecnh dao \u0111\u1ed9ng c\u00f3 d\u1ea1ng x = 10cos(\u03c0t) trong \u0111\u00f3 x t\u00ednh b\u1eb1ng cm v\u00e0 t t\u00ednh b\u1eb1ng gi\u00e2y. G\u1ed1c th\u1eddi gian l\u00e0 l\u00fac v\u1eadt<\/p>\n<p>A. v\u1eadt \u0111ang c\u00f3 v\u1eadn t\u1ed1c b\u1eb1ng 0.<\/p>\n<p>B. v\u1eadt \u0111ang \u1edf bi\u00ean \u0111\u1ed9 \u00e2m<\/p>\n<p>C. v\u1eadt \u0111ang \u1edf bi\u00ean \u0111\u1ed9 d\u01b0\u01a1ng.<\/p>\n<p>D. v\u1eadt qua v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng v\u00e0 chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u \u00e2m.<\/p>\n<p style=\"text-align: center;\"><strong>Gi\u1ea3i<\/strong><\/p>\n<p>$\\left\\{ \\begin{align} &amp; t=0 \\\\ &amp; x=10c\\text{os}\\left( \\pi .0 \\right)=10\\left( cm \\right) \\\\ &amp; v=-5\\pi .\\sin \\left( \\pi .0 \\right)=0 \\\\ \\end{align} \\right.$<\/p>\n<p>Ch\u1ecdn D.<\/p>\n<p><strong>V\u00ed d\u1ee5 4: <\/strong>M\u1ed9t v\u1eadt dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a v\u1edbi ph\u01b0\u01a1ng tr\u00ecnh x = 2cos(\u03c0t &#8211; 2\u03c0\/3)cm. G\u1ed1c th\u1eddi gian l\u00e0 l\u00fac v\u1eadt c\u00f3<\/p>\n<p>A. li \u0111\u1ed9 x = A\/2, chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u d\u01b0\u01a1ng<\/p>\n<p>B. li \u0111\u1ed9 x = A\/2, chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u \u00e2m.<\/p>\n<p>C. li \u0111\u1ed9 x = &#8211; A\/2, chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u d\u01b0\u01a1ng.<\/p>\n<p>D. li \u0111\u1ed9 x = &#8211; A\/2, chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u \u00e2m.<\/p>\n<p style=\"text-align: center;\"><strong>Gi\u1ea3i<\/strong><\/p>\n<p>$\\begin{array}{l} x = 2\\cos \\left( {\\pi t &#8211; \\frac{{2\\pi }}{3}} \\right)\\left( {cm} \\right)\\\\ \\to v = &#8211; 2\\pi \\sin \\left( {\\pi t &#8211; \\frac{{2\\pi }}{3}} \\right)\\left( {\\frac{{cm}}{s}} \\right)\\\\ t = 0 \\to \\left\\{ \\begin{array}{l} x = 2\\cos \\left( {\\pi .0 &#8211; \\frac{{2\\pi }}{3}} \\right) = &#8211; \\frac{A}{2}\\\\ v = &#8211; 2\\pi \\sin \\left( {\\pi .0 &#8211; \\frac{{2\\pi }}{3}} \\right) &gt; 0 \\end{array} \\right. \\end{array}$<\/p>\n<p>Ch\u1ecdn C.<\/p>\n<p><strong>V\u00ed d\u1ee5 5: <\/strong>Ph\u01b0\u01a1ng tr\u00ecnh dao \u0111\u1ed9ng c\u00f3 d\u1ea1ng x = Acos(wt + \u03c0\/3), trong \u0111\u00f3 x t\u00ednh b\u1eb1ng cm v\u00e0 th\u1eddi gian t\u00ednh b\u1eb1ng gi\u00e2y. G\u1ed1c th\u1eddi gian l\u00e0 l\u00fac v\u1eadt c\u00f3<\/p>\n<p>A. li \u0111\u1ed9 x = A\/2, chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u d\u01b0\u01a1ng.<\/p>\n<p>B. li \u0111\u1ed9 x = A\/2, chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u \u00e2m.<\/p>\n<p>C. li \u0111\u1ed9 x = &#8211; A\/2, chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u d\u01b0\u01a1ng.<\/p>\n<p>D. li \u0111\u1ed9 x = &#8211; A\/2, chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u \u00e2m<\/p>\n<p style=\"text-align: center;\"><strong>Gi\u1ea3i<\/strong><\/p>\n<p>$\\begin{array}{l} x = A\\cos \\left( {\\omega t + \\frac{\\pi }{3}} \\right)\\left( {cm} \\right)\\\\ \\to v = &#8211; A.\\pi \\sin \\left( {\\omega t + \\frac{\\pi }{3}} \\right)\\left( {\\frac{{cm}}{s}} \\right)\\\\ t = 0 \\to \\left\\{ \\begin{array}{l} x = 2\\cos \\left( {\\omega .0 + \\frac{\\pi }{3}} \\right) = &#8211; \\frac{A}{2}\\\\ v = &#8211; 2\\pi \\sin \\left( {\\omega .0 + \\frac{\\pi }{3}} \\right) &lt; 0 \\end{array} \\right. \\end{array}$<\/p>\n<p>Ch\u1ecdn B.<\/p>\n<p><strong>V\u00ed d\u1ee5 6: <\/strong>Ph\u01b0\u01a1ng tr\u00ecnh dao \u0111\u1ed9ng c\u00f3 d\u1ea1ng x = &#8211; 2sin(\u03c0t &#8211; \u03c0\/4) trong \u0111\u00f3 x t\u00ednh b\u1eb1ng cm v\u00e0 t t\u00ednh b\u1eb1ng gi\u00e2y. G\u1ed1c th\u1eddi gian l\u00e0 l\u00fac v\u1eadt c\u00f3<\/p>\n<p>A. v\u1eadn t\u1ed1c v\u00e0 gia t\u1ed1c ng\u01b0\u1ee3c chi\u1ec1u d\u01b0\u01a1ng tr\u1ee5c t\u1ecda \u0111\u1ed9.<\/p>\n<p>B. v\u1eadn t\u1ed1c v\u00e0 li \u0111\u1ed9 ng\u01b0\u1ee3c chi\u1ec1u tr\u1ee5c t\u1ecda \u0111\u1ed9.<\/p>\n<p>C. v\u1eadn t\u1ed1c v\u00e0 gia t\u1ed1c c\u00f3 c\u00f9ng chi\u1ec1u tr\u1ee5c t\u1ecda \u0111\u1ed9.<\/p>\n<p>D. v\u1eadn t\u1ed1c v\u00e0 li \u0111\u1ed9 c\u00f9ng chi\u1ec1u tr\u1ee5c t\u1ecda \u0111\u1ed9.<\/p>\n<p style=\"text-align: center;\"><strong>Gi\u1ea3i<\/strong><\/p>\n<p>$\\begin{array}{l} \\left\\{ \\begin{array}{l} t = 0\\\\ x = &#8211; 2\\sin (\\pi .t &#8211; \\frac{\\pi }{4}) \\end{array} \\right.\\\\ \\to \\left\\{ \\begin{array}{l} t = 0\\\\ a = 2{\\pi ^2}\\sin \\left( {\\pi t &#8211; \\frac{\\pi }{4}} \\right)\\\\ v = &#8211; 2\\pi .c{\\rm{os}}\\left( {\\pi .t &#8211; \\frac{\\pi }{4}} \\right) \\end{array} \\right.\\,\\\\ \\to \\left\\{ \\begin{array}{l} a = 2{\\pi ^2}\\sin \\left( {\\pi .0 &#8211; \\frac{\\pi }{4}} \\right) &lt; 0\\\\ v = &#8211; 2\\pi .c{\\rm{os}}\\left( {\\pi .0 &#8211; \\frac{\\pi }{4}} \\right) &lt; 0 \\end{array} \\right. \\end{array}$<\/p>\n<p>Ch\u1ecdn A.<\/p>\n<p><strong>V\u00ed d\u1ee5 7: <\/strong>M\u1ed9t v\u1eadt dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f3 ph\u01b0\u01a1ng tr\u00ecnh x = Acos(\u03c9t + \u03c6), trong \u0111\u00f3 A, \u03c9, \u03c6 l\u00e0 h\u1eb1ng s\u1ed1. Vect\u01a1 gia t\u1ed1c v\u00e0 vect\u01a1 v\u1eadn t\u1ed1c ng\u01b0\u1ee3c chi\u1ec1u d\u01b0\u01a1ng c\u1ee7a tr\u1ee5c t\u1ecda \u0111\u1ed9 khi<\/p>\n<p>A. v\u1eadt \u0111i t\u1eeb x = &#8211; A \u0111\u1ebfn x = A. B. v\u1eadt \u0111i t\u1eeb x = &#8211; A \u0111\u1ebfn x = 0.<\/p>\n<p>C. v\u1eadt \u0111i t\u1eeb x = A \u0111\u1ebfn x = &#8211; A. D. v\u1eadt \u0111i t\u1eeb x = A \u0111\u1ebfn x = 0.<\/p>\n<p style=\"text-align: center;\"><strong>Gi\u1ea3i<\/strong><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-619 alignnone size-medium aligncenter\" src=\"https:\/\/giapsgk.com\/chuyen-de\/wp-content\/uploads\/2025\/08\/image.png\" alt=\"\" width=\"300\" height=\"75\" srcset=\"https:\/\/giapsgk.com\/chuyen-de\/wp-content\/uploads\/2025\/08\/image.png 348w, https:\/\/giapsgk.com\/chuyen-de\/wp-content\/uploads\/2025\/08\/image-300x75.png 300w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/p>\n<p>Ta bi\u1ebft a = &#8211; \u03c92x n\u00ean a lu\u00f4n tr\u00e1i d\u1ea5u v\u1edbi x.<\/p>\n<p>A. v\u1eadt \u0111i t\u1eeb x = 5 \u0111\u1ebfn x = &#8211; 10 \u2192 vecto v lu\u00f4n ng\u01b0\u1ee3c chi\u1ec1u d\u01b0\u01a1ng Ox \u2192 lo\u1ea1i.<\/p>\n<p>B. V\u1eadt \u0111i t\u1eeb x = &#8211; 6 \u0111\u1ebfn x = &#8211; 3 \u2192 vecto v lu\u00f4n c\u00f9ng chi\u1ec1u d\u01b0\u01a1ng Ox v\u00e0 vecto gia t\u1ed1c lu\u00f4n c\u00f9ng chi\u1ec1u Ox\u2192 nh\u1eadn<\/p>\n<p>C. V\u1eadt \u0111i t\u1eeb x = 6 cm \u0111\u1ebfn x = 8 cm \u2192 vecto v lu\u00f4n c\u00f9ng chi\u1ec1u d\u01b0\u01a1ng Ox, tuy nhi\u00ean vecto gia t\u1ed1c lu\u00f4n ng\u01b0\u1ee3c chi\u1ec1u Ox \u2192 lo\u1ea1i<\/p>\n<p>D. v\u1eadt \u0111i t\u1eeb x = 10 cm \u0111\u1ebfn x = 0 \u2192 vecto v lu\u00f4n c\u00f9ng chi\u1ec1u d\u01b0\u01a1ng Ox \u2192 lo\u1ea1i<\/p>\n<p>Ch\u1ecdn D.<\/p>\n<p><strong>V\u00ed d\u1ee5 8:<\/strong><\/p>\n<p>M\u1ed9t v\u1eadt dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f3 ph\u01b0\u01a1ng tr\u00ecnh x = 4cos(\u03c0t &#8211; \u03c0\/12), v\u1edbi x t\u00ednh b\u1eb1ng cm v\u00e0 t t\u00ednh b\u1eb1ng s. Li \u0111\u1ed9 v\u00e0 v\u1eadn t\u1ed1c c\u00f3 c\u00f9ng gi\u00e1 tr\u1ecb d\u01b0\u01a1ng<\/p>\n<p>A. v\u1eadt \u0111i t\u1eeb x = 2,5 cm \u0111\u1ebfn x = 1 cm.<\/p>\n<p>B. v\u1eadt \u0111i t\u1eeb x = &#8211; 3 cm \u0111\u1ebfn x = 3 cm.<\/p>\n<p>C. v\u1eadt \u0111i t\u1eeb x = 1,25 cm \u0111\u1ebfn x = 3 cm.<\/p>\n<p>D. v\u1eadt \u0111i t\u1eeb x = &#8211; 4 cm \u0111\u1ebfn x = 4 cm.<\/p>\n<p style=\"text-align: center;\"><strong>Gi\u1ea3i<\/strong><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-622 alignnone size-medium aligncenter\" src=\"https:\/\/giapsgk.com\/chuyen-de\/wp-content\/uploads\/2025\/08\/giapsgk-y-nghia-cua-cac-dai-luong-trong-vat-li-1.png\" alt=\"H\u00ecnh \u1ea3nh - y-nghia-cua-cac-dai-luong-trong-vat-li\" width=\"314\" height=\"95\" \/><\/p>\n<p>Ta bi\u1ebft a = &#8211; \u03c92x n\u00ean a lu\u00f4n tr\u00e1i d\u1ea5u v\u1edbi x.<\/p>\n<p>A. v\u1eadt \u0111i t\u1eeb x = 2,5 cm \u0111\u1ebfn x = 1 cm \u2192 li \u0111\u1ed9 lu\u00f4n d\u01b0\u01a1ng v\u00e0 vecto v\u1eadn t\u1ed1c ng\u01b0\u1ee3c chi\u1ec1u Ox n\u00ean lu\u00f4n nh\u1eadn gi\u00e1 tr\u1ecb \u00e2m \u2192 lo\u1ea1i.<\/p>\n<p>B. v\u1eadt \u0111i t\u1eeb x = &#8211; 3 cm \u0111\u1ebfn x = 0 cm \u2192 li \u0111\u1ed9 l\u00fac \u00e2m\u2192 lo\u1ea1i<\/p>\n<p>C. v\u1eadt \u0111i t\u1eeb x = 1,25 cm \u0111\u1ebfn x = 3 cm \u2192 li \u0111\u1ed9 lu\u00f4n d\u01b0\u01a1ng v\u00e0 vecto v lu\u00f4n c\u00f9ng chi\u1ec1u d\u01b0\u01a1ng Ox n\u00ean v lu\u00f4n nh\u1eadn gi\u00e1 tr\u1ecb d\u01b0\u01a1ng\u2192nh\u1eadn<\/p>\n<p>D. v\u1eadt \u0111i t\u1eeb x = &#8211; 4 cm \u0111\u1ebfn x = 0\u2192 li \u0111\u1ed9 l\u00fac \u00e2m\u2192 lo\u1ea1i<\/p>\n<p>Ch\u1ecdn C.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>V\u00ed d\u1ee5 1: Ph\u01b0\u01a1ng tr\u00ecnh dao \u0111\u1ed9ng c\u00f3 d\u1ea1ng x = 2cos(2\u03c0t) trong \u0111\u00f3 x t\u00ednh b\u1eb1ng cm v\u00e0 t t\u00ednh b\u1eb1ng gi\u00e2y. G\u1ed1c th\u1eddi gian l\u00e0 l\u00fac v\u1eadt A. v\u1eadt \u0111ang \u1edf bi\u00ean \u0111\u1ed9 d\u01b0\u01a1ng. B. v\u1eadt \u0111ang \u1edf bi\u00ean \u0111\u1ed9 \u00e2m. C. v\u1eadt \u0111ang \u1edf VTCB chuy\u1ec3n \u0111\u1ed9ng theo chi\u1ec1u d\u01b0\u01a1ng. D. v\u1eadt &#8230; <a title=\"\u00dd ngh\u0129a c\u1ee7a c\u00e1c \u0111\u1ea1i l\u01b0\u1ee3ng trong v\u1eadt l\u00ed\" class=\"read-more\" href=\"https:\/\/giapsgk.com\/chuyen-de\/dao-dong\/dao-dong-dieu-hoa\/y-nghia-cua-cac-dai-luong-trong-vat-li\/\" aria-label=\"\u0110\u1ecdc th\u00eam v\u1ec1 \u00dd ngh\u0129a c\u1ee7a c\u00e1c \u0111\u1ea1i l\u01b0\u1ee3ng trong v\u1eadt l\u00ed\">\u0110\u1ecdc ti\u1ebfp<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":580,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-611","page","type-page","status-publish"],"_links":{"self":[{"href":"https:\/\/giapsgk.com\/chuyen-de\/wp-json\/wp\/v2\/pages\/611","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/giapsgk.com\/chuyen-de\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/giapsgk.com\/chuyen-de\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/giapsgk.com\/chuyen-de\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/giapsgk.com\/chuyen-de\/wp-json\/wp\/v2\/comments?post=611"}],"version-history":[{"count":3,"href":"https:\/\/giapsgk.com\/chuyen-de\/wp-json\/wp\/v2\/pages\/611\/revisions"}],"predecessor-version":[{"id":623,"href":"https:\/\/giapsgk.com\/chuyen-de\/wp-json\/wp\/v2\/pages\/611\/revisions\/623"}],"up":[{"embeddable":true,"href":"https:\/\/giapsgk.com\/chuyen-de\/wp-json\/wp\/v2\/pages\/580"}],"wp:attachment":[{"href":"https:\/\/giapsgk.com\/chuyen-de\/wp-json\/wp\/v2\/media?parent=611"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}