如图所示,在x轴上方存在着垂直于纸面向里、磁感应强度为B的匀强磁场,一个不计重力

题型:选择题

问题:

如图所示,在x轴上方存在着垂直于纸面向里、磁感应强度为B的匀强磁场,一个不计重力的带电粒子从坐标原点O处以速度v进入磁场,粒子进人磁场时的速度方向垂直于磁场且与x轴正方向成120°角,若粒子穿过y轴正半轴后在磁场中到x轴的最大距离为a,则该粒子的比荷和所带电荷的正负是(  )

A.,正电荷

B.,正电荷

C.,负电荷

D.,负电荷

考点:带电粒子在匀强磁场中的运动
题型:选择题
在△ABC中,角A,B,C的对边分别是a,b,c,且b2=ac=a2-c2+bc.
(1)求
bsinB
c
的值;
(2)试判断△ABC的形状,并说明理由.
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司法执行是指司法机构依据生效司法文书,将基金份额持有人持有的基金份额强制划转给其他()。

A.自然人

B.法人

C.社会团体

D.其他组织

题型:选择题

阅读下面短文,根据上下文填入适当的词语,或使用括号中的词语的适当形式填空,并将答案填写在答题卡上标号为36-45的相应位置。

Thirteen-year-old Andrew will never forget that Saturday. He was relaxing on his family’s sofa with his sister, Susan. Suddenly the heater exploded. His sister, who was unhurt, managed to pull   26  away from the fire   27  his mum dialed for an ambulance.  28  ambulance soon arrived and rushed him to Children’s Hospital   29  he was operated on immediately.

Doctors told his mum there was little chance of Andrew being able to walk again. The damage to his body was so bad and the cuts in his legs so deep that the   30 (operate) took 11 hours. After a couple of weeks, he   31  (allow) to go home but had to spend the next six weeks in a wheelchair.  32  the help of his doctor, this brave young boy returned to school after only two and a half months.   33  (look) back on the accident, Andrew says he believes children can do   34  they want   35  they put their mind to it.

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“五四”前后西方文化大量被引进,新的政治、科技词语大量甲。随着改革开放的不断深入,经济方面的新词语尤为活跃,如“知识经济”、“特区”、“下岗”、“炒鱿鱼”等。核裂变之际,各种微粒高速碰撞,便产生新的微粒。语言现象乙。依次填入甲、乙两处的词语,最恰当的是()。

A.涌现与此雷同

B.诞生与此雷同

C.诞生与之类似

D.涌现与之类似

题型:选择题

对格式条款的解释应遵循()原则。

A.格式条款的一般解释

B.不利于格式条款提供人的解释

C.非格式条款优于格式条款的原则

D.不利于非格式条款提供人的解释

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