30、一块三角形木块B静止在水平桌面上,而长方体木块A静止在B的斜面上,如图.下列说法正确的是（ ） 多选30、一块三角形木块B静止在水平桌面上,而长方体木块A静止在B的斜面上,如图.下列说

30、一块三角形木块B静止在水平桌面上,而长方体木块A静止在B的斜面上,如图.下列说法正确的是（ ） 多选30、一块三角形木块B静止在水平桌面上,而长方体木块A静止在B的斜面上,如图.下列说
30、一块三角形木块B静止在水平桌面上,而长方体木块A静止在B的斜面上,如图.下列说法正确的是（ ） 多选
30、一块三角形木块B静止在水平桌面上,而长方体木块A静止在B的斜面上,如图.下列说法正确的是（ ）
A水平桌面对的B支持力大小等于A与B的物重之和
B、水平桌面受到B的压力并受到A的压力
C、B对A的支持力与A的重力不是一对平衡力
D、就水平桌面对B的支持力而言,B是受力物体,A也是受力物体
请解释A正确的原因!

30、一块三角形木块B静止在水平桌面上,而长方体木块A静止在B的斜面上,如图.下列说法正确的是（ ） 多选30、一块三角形木块B静止在水平桌面上,而长方体木块A静止在B的斜面上,如图.下列说
静止物体.一定是受力平衡.垂直向上的支持力和垂直向下的重力就是一对平衡力.平衡力大小相等,方向相反,作用在同一物体上.最简单就是把A和B看成一个物体,也就是把A和B看成以整体.也可以对B物体进行受力分析：静止,受力平衡,B受到垂直向下的力有B自身重力加上来自A的压力,压力大小等于A的重力；垂直向上的力只有桌面对B的支持力.所以“水平桌面对的B支持力大小等于A与B的物重之和 ”

用整体法，在竖直方向上整体静止处于平衡状态，所以竖直向下的重力和竖直向上的支持力等大，

A (将AB看成一个物体。画出受力图）

Tour de France yellow jersey the next day the Norwegian sprint Reggie,christian louboutin 2011
Norway,
The conclusion of 2011 Tour de France time trial competition for your second group stage,...

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Tour de France yellow jersey the next day the Norwegian sprint Reggie,christian louboutin 2011
Norway,
The conclusion of 2011 Tour de France time trial competition for your second group stage, Germany, Norway sprint master Hushu Fu Jia Ming led the U.S. team to get the very first 24 minutes and 48 seconds,discount christian louboutin shoes, which can be good because the Tour de France team that won the very first match Section title. British Sky team to a second 24 minutes 52 seconds,christian louboutin shop online, the U.S. team also BMC race 24 minutes 52 seconds in third. Hu Shufu Germany in 5 hours and 6 minutes and 25 seconds behind individual total score of the very first, riding a yellow jersey to use a collar,cheap christian louboutin shoes, even though defending champion Kang Tade ranking has improved, he was a 5 hours 8 minutes 7 seconds at No. 75 bit, but the other favorites to win the Andy - Shrek the space is widening substantially 98 seconds, which ranked the rapid surge in 5 hours and 6 minutes and 29 seconds from yesterday's immediate concern the way in which No. 33 No. 10.
For today's game in Laisa Er, using they time trial rules, the whole track 23 km long. Competition within the 14:30 pm local time (GMT 20:30) began, based on tournament rules, 22 teams every interval of 7 minutes from one for the evening nearby time 16:57 (GMT 22:57) Yesterday, the very first row of the first stage with the Belgian Lotto team final departure. Beginning today, the very first team in Denmark Saxo Bank team, even though yesterday, no more than great, but Zhezhi veteran teams are not affected, in Kang Tade under the leadership of their method to ride out 9 minutes 13 seconds good outcomes,christian louboutin high heels, the last 25 minutes 16 seconds to reach the conclusion.
This result's quite good, the back up team following another tough appear at their implementation of effective breakthrough, nevertheless the team issued the sixth spending - the Dutch team is the first to attain Joan banks beyond their lead with 25 minutes 00 seconds 16 seconds Saxo Bank team get to the end. Next game is more intense competition.

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