<p><a href="https://www.youtube.com/watch?v=WgHmqv_-UbQ" target="_blank">https://www.youtube.com/watch?v=WgHmqv_-UbQ</a></p><p><a href="https://www.youtube.com/watch?v=DD_8Jm5pTLk" target="_blank">https://www.youtube.com/watch?v=DD_8Jm5pTLk</a>&nbsp;дараах бичлэгүүдийг ажиглаж тэмдэглэл хөтлөх<br></p><p><a href="https://phet.colorado.edu/sims/html/gravity-and-orbits/latest/gravity-and-orbits_en.html" target="_blank">https://phet.colorado.edu/sims/html/gravity-and-orbits/latest/gravity-and-orbits_en.html</a>&nbsp;туршилт хийж тэмдэглэл хөтлөх<br></p><p>Сурах бичгийн 102-104-р хуудсыг уншиж тэмдэглэл хөтлө</p><p><a href="http://econtent.edu.mn/book/7rangi" target="_blank">http://econtent.edu.mn/book/7rangi</a><br></p>