Sự rơi tự do - Bài tập trung bình

Home Lớp 10 Vật lý 10 - Sách kết nối tri thức Bài 10: Sự rơi tự doBài tập trung bình

{"common":{"save":0,"post_id":"6347","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"5916","mon_id":"1158790","chapter_id":"1158795","post_id":"6347","question":"Mô\u0323t v\u1eadt r\u01a1i t\u1ef1 do t\u1eeb \u0111\u1ed9 cao h xu\u1ed1ng \u0111\u1ea5t. Ch\u1ecdn tr\u1ee5c Ox có ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng, chi\u1ec1u d\u01b0\u01a1ng h\u01b0\u1edbng t\u1eeb trên xu\u1ed1ng. Công th\u1ee9c tính quãng \u0111\u01b0\u1eddng \u0111i c\u1ee7a v\u1eadt r\u01a1i t\u1ef1 do là<\/p>","options":["A. $s=\\nu_0+gt$<\/span>","B. $s={1\\over2}gt^2$<\/span>","C. $s={1\\over2}\\nu_0t$<\/span>","D. $s=\\nu_0t$<\/span>"],"correct":"2","level":"2","hint":"Công th\u1ee9c tính quãng \u0111\u01b0\u1eddng \u0111i c\u1ee7a v\u1eadt r\u01a1i t\u1ef1 do là  <\/p>","answer":"Ch\u1ecdn B.<\/strong><\/span> Chi\u1ec1u d\u01b0\u01a1ng h\u01b0\u1edbng t\u1eeb trên xu\u1ed1ng => s = d =>  $s={1\\over2}gt^2$<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"147","test":"0","date":"2022-10-26 15:04:44","option_type":"math","len":0},{"id":"5917","mon_id":"1158790","chapter_id":"1158795","post_id":"6347","question":"Mô\u0323t v\u1eadt r\u01a1i t\u1ef1 do t\u1eeb \u0111\u1ed9 cao h xu\u1ed1ng \u0111\u1ea5t, vâ\u0323n tô\u0301c cu\u0309a vâ\u0323t ngay tr\u01b0\u01a1\u0301c khi cha\u0323m \u0111â\u0301t la\u0300 <\/p>","options":["A. $\\nu=\\sqrt{2gh}$<\/span>","B. $\\nu=\\sqrt{h\\over2g}$<\/span>","C. $\\nu=\\sqrt{2g\\over h}$<\/span>","D. $\\nu=\\sqrt{gh\\over2}$<\/span>"],"correct":"1","level":"2","hint":"$\\nu=\\sqrt{2gh}$<\/span><\/p>","answer":"Ch\u1ecdn A.<\/strong><\/span> S\u1eed d\u1ee5ng công th\u1ee9c:  $\\nu^2-\\nu_0^2=2ad$<\/span> Vì v\u1eadt r\u01a1i t\u1ef1 do nên      $\\begin{cases}\\nu_0=0\\\\a=g\\\\d=h\\end{cases}\\Rightarrow \\nu^2=2gh \\Rightarrow \\nu=\\sqrt{2gh}$<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"147","test":"0","date":"2022-10-26 15:10:45","option_type":"math","len":0},{"id":"5918","mon_id":"1158790","chapter_id":"1158795","post_id":"6347","question":"Trong các công th\u1ee9c tính th\u1eddi gian v\u1eadt r\u01a1i t\u1ef1 do t\u1eeb \u0111\u1ed9 cao h cho sau \u0111ây, công th\u1ee9c nào sai<\/strong>?<\/p>","options":["A. $t={\\nu\\over g}$<\/span>","B. $t={h\\over \\nu_{tb}}$<\/span>","C. $t=\\sqrt{2h\\over g}$<\/span>","D. $t=\\sqrt{2gh}$<\/span>"],"correct":"4","level":"2","hint":"$t=\\sqrt{2gh}$<\/span>  là công th\u1ee9c sai.<\/p>","answer":"Ch\u1ecdn D.<\/strong><\/span> Vì v\u1eadt r\u01a1i t\u1ef1 do nên     $\\begin{cases}\\nu_0=0\\\\a=g\\\\d=h\\end{cases}$<\/span> + T\u1eeb công th\u1ee9c $\\nu=\\nu_0+at=gt \\Rightarrow t={\\nu\\over g}$<\/span>    => A \u0111úng + T\u1eeb công th\u1ee9c  $\\nu_{tb}={d\\over t}={h\\over t}\\Rightarrow t={h\\over \\nu_{tb}}$<\/span>  => B \u0111úng + T\u1eeb công th\u1ee9c  $d=\\nu_0t+{1\\over 2}at^2 \\Leftrightarrow h={1\\over2}gt^2 \\Rightarrow t=\\sqrt{2h\\over g}$<\/span>   => C \u0111úng, D sai.<\/p>","type":"choose","extra_type":"classic","user_id":"147","test":"0","date":"2022-10-27 02:08:24","option_type":"math","len":0}]}