杆AB长为ι，质量为m，图4-64所示瞬时点A处的速度为ν，则杆AB动量的大小为（）。https://assets.asklib.com/psource/2015103014425046008.jpg

A . A B . B C . C D . D

A . ['mvB . 2mvC .https://assets.asklib.com/psource/2015102713295090764.jpg mvD . mv／https://assets.asklib.com/psource/2015102713295090764.jpg

A .https://assets.asklib.com/psource/201510301440198304.jpg B .https://assets.asklib.com/psource/2015103014403321493.jpg C .https://assets.asklib.com/psource/2015103014405072692.jpg D .https://assets.asklib.com/psource/2015103014410294262.jpg

A . FNA=FNB=0 B . B.FNA=FNB≠0 C . FNA≤FNB D . FNA≥FNB

A . A B . B C . C D . D

A . ['['https://assets.asklib.com/psource/201510301504278200.jpg B .https://assets.asklib.com/psource/2015103015044437078.jpg C . mι2ωD .https://assets.asklib.com/psource/2015103015045744987.jpg

A . A B . B C . C D . D

A . A B . B C . C D . D

A .https://assets.asklib.com/psource/2015103014503984624.jpg B .https://assets.asklib.com/psource/2015103014505084240.jpg C .https://assets.asklib.com/psource/2015103014510485319.jpg D .https://assets.asklib.com/psource/2015103014512148828.jpg

A .https://assets.asklib.com/images/image2/201705110946166076.png B .https://assets.asklib.com/images/image2/2017051109461984184.png C .https://assets.asklib.com/images/image2/2017051109462167686.png D .https://assets.asklib.com/images/image2/2017051109462264555.png

A . ['['0B .https://assets.asklib.com/psource/2015110210461670074.png C .https://assets.asklib.com/psource/201511021046197517.png D .https://assets.asklib.com/psource/2015110210462335569.png

A . ['2mgB . mgC .https://assets.asklib.com/psource/2015103015072531074.jpg D .https://assets.asklib.com/psource/2015103015073718551.jpg

A . A B . B C . C D . D

A .https://assets.asklib.com/psource/2015110110585186645.jpg B .https://assets.asklib.com/psource/2015110110590351835.jpg C .https://assets.asklib.com/psource/2015110110591689042.jpg D .https://assets.asklib.com/psource/201511011059284507.jpg

A . A B . B C . C D . D

<img src='https://img2.soutiyun.com/ask/uploadfile/5088001-5091000/3594214f7d306b5ff132a506e104e731.png' /><img src='https://img2.soutiyun.com/ask/uploadfile/5088001-5091000/02b0a48bc9625b5ad5951730c2d41912.png' />

<img src='https://img2.soutiyun.com/shangxueba/ask/18627001-18630000/18627235/2016071917373619874.jpg' /><img src='https://img2.soutiyun.com/shangxueba/ask/18627001-18630000/18627235/201607191737384184.jpg' /> A．A B． B C． C D． D

A．<img src='https://img2.soutiyun.com/shangxueba/ask/1989001-1992000/1990848/ct_jgzjgysm_jgzjgyschoose_00179(20093)2.jpg' /> B．<img src='https://img2.soutiyun.com/shangxueba/ask/1989001-1992000/1990848/ct_jgzjgysm_jgzjgyschoose_00179(20093)3.jpg' /> C．<img src='https://img2.soutiyun.com/shangxueba/ask/1989001-1992000/1990848/ct_jgzjgysm_jgzjgyschoose_00179(20093)4.jpg' /> D．<img src='https://img2.soutiyun.com/shangxueba/ask/1989001-1992000/1990848/ct_jgzjgysm_jgzjgyschoose_00179(20093)5.jpg' />

<img src='https://img2.soutiyun.com/ask/2020-12-09/976394857430461.png' />

<img src='https://img2.soutiyun.com/shangxueba/ask/19098001-19101000/19099118/2015103014425046008.jpg' /> A. ['mν B. 2mν C.<img src='https://img2.soutiyun.com/shangxueba/ask/19098001-19101000/19099118/201510301443098930.jpg' /> D.<img src='https://img2.soutiyun.com/shangxueba/ask/19098001-19101000/19099118/2015103014431950221.jpg' />

<img src='https://img2.soutiyun.com/ask/2021-03-19/984995037369554.png' />

A．0 B．；0 C．0

题11-30图(a)所示质量分别为m和2m，长度分别为I和2l的均质细杆OA和AB在A点光滑铰接，OA杆的O端为光滑固定铰链。AB杆的B端放在光滑水平面上。初瞬时，OA杆水平，AB杆铅直。由于初位移的微小扰动，AB杆的B端无初速地向右滑动，试求当OA杆运动到铅垂位置时，A点处的约束力。 <img src='https://img2.soutiyun.com/ask/2020-12-17/977084883102405.png' />

长为l,质量为m的均质杆AB和BC用铰链B连接，并用铰链A固定,位于平衡位置，如题10-28图(a)所示。今在C端作用一水平力F,试求此瞬时，两杆的角加速度。 <img src='https://img2.soutiyun.com/ask/2020-12-17/977075668776376.png' />