一个质量mA为4kg的木板A放在水平面C上,木板与水平面间的动摩擦因数u=0.24,木板右上端放着质量m B为1.0k的小物块B（视为质点）,它们均处于静止状态,木板A 突然受到水平向右的瞬时冲量I=12N．s

一个质量mA为4kg的木板A放在水平面C上,木板与水平面间的动摩擦因数u=0.24,木板右上端放着质量m B为1.0k的小物块B（视为质点）,它们均处于静止状态,木板A 突然受到水平向右的瞬时冲量I=12N．s
一个质量mA为4kg的木板A放在水平面C上,木板与水平面间的动摩擦因数u=0.24,木板右上端放着质量m B为1.0k的小物块B（视为质点）,它们均处于静止状态,木板A 突然受到水平向右的瞬时冲量I=12N．s作用后开始运动.当小物块B滑落木板时,木板的动能EKA=8.0J,小物块的动能EKB=0.50J,重力加速度取10m/s2.求：
1）瞬时冲量作用结束时木板的速度v0；
2）木板的长度L

一个质量mA为4kg的木板A放在水平面C上,木板与水平面间的动摩擦因数u=0.24,木板右上端放着质量m B为1.0k的小物块B（视为质点）,它们均处于静止状态,木板A 突然受到水平向右的瞬时冲量I=12N．s
1）I=mB*V0
V0=I/mB=12 / 1=12 m/s
2）对B,F*SB=EkB
F* t =mB*VB
对A,[ F+u*(mA＋mB*)g ]*SA=(mA*V0^2 / 2)－EkA
[ F+u*(mA＋mB*)g ]* t =mA*(V0－VA)
SA－SB=L
以上五式联立,得
L=21.3125米 　文字输入有限.

3 rockets overnight turned young military
McHale
The key reason why a lot of competition for your Rockets who select McHale, took a pricy to him and the young players go along nicely, and good...

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3 rockets overnight turned young military
McHale
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His greatest to show young players adjust. "Rockets signed him I believe is a very wise choice, simply because he is the highest basketball IQ I've seen one," Rockets coach hired McHale as the day, his buddy Hoey Borg stated these words. Hoiberg has two seasons in Minnesota campaign, retired following he became Minnesota's assistant gm. For McHale's abilities and characteristics, Hoiberg know too much could be stated. "Kevin McHale will be the best post player mentor, nobody better than him, as soon as your team features a coach he was, and that's the gospel with the young post player who had," Hoiberg said. Hoiberg was most impressed by is always that McHale on Kevin Garnett, Al Jefferson,Nike Air Presto, and Musharraf's tune. Garnett entered the NBA (microblogging), when McHale has spent countless hours Danlian Garnett. Garnett later to turn out to be the Titans inside superb offensive and defensive, can't do with out McHale's pay. Hoiberg came once the Timberwolves, Garnett has turn out to be well-known, but McHale Garnett still frequently give some pointers.
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