试题与答案

如图所示,在xoy平面内,第Ⅲ象限内的直线OM是电场与磁场的边界,OM与负x轴成

题型:计算题

题目:

如图所示,在xoy平面内,第Ⅲ象限内的直线OM是电场与磁场的边界,OM与负x轴成45°角。在x<0且OM的左侧空间存在着负x方向的匀强电场E,场强大小为0.32N/C; 在y<0且OM的右侧空间存在着垂直纸面向里的匀强磁场B,磁感应强度大小为0.1T。一不计重力的带负电的微粒,从坐标原点O沿y轴负方向以v0=2×103m/s的初速度进入磁场,最终离开电磁场区域。已知微粒的电荷量q=5×10-18 C,质量m=1×10-24 kg,求:

(1)带电微粒第一次经过磁场边界的位置坐标;

(2)带电微粒在磁场区域运动的总时间;

(3)带电微粒最终离开电磁场区域的位置坐标。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:E解析:ALI/ARDS无效腔量/潮气量>0.5。

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Here in the U. S. a project of moving the government a few hundred miles to the southwest proceeds apace, under the supervision of Senator Robert Byrd of West Virginia. Apart from the usual highways and parks, Byrd has taken a special interest in transplanting pieces of federal agencies from metropolitan Washington to his home state.

Strangely, Byrd’s little experiment in de-Washingtonization has become the focus of outrage among the very people who are otherwise most critical of Washington and its ways. To these critics, it is the very symbol of congressional arrogance of power, isolation from reality, contempt for the voters, and so on, and demonstrates the need for term limits if not lynching.

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D. "luxuries."

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