The Right Thing “ Hi , Mrs , Grady ,” said Mark when their neighbor opened her door. “ Would you like us to shovel your sidewalk and driveway ?” Shoveling was Jamie’s idea , a way to earn enough money for the new Ocean Kingdom video game that came out the next day . Mrs .Grady was happy , “ That would be wonderful , boys . I think the job is getting to be too much for me . “It will cost 10 dollars ,” Jamie said .” If that’s OK “, Mark added . ‘ Oh dear , “ Mrs. Grady said disappointedly , “ I haven’t been able to get to the bank . I can offe
如图所示,实线表示在竖直平面内匀强电场的电场线,电场线与水平方向成α角,水平方向的匀强磁场与电场正交,有一带电液滴沿斜向上的虚线l做直线运动,l与水平方向成β角,且α>β,则下列说法中错误的是
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A.
液滴一定做匀变速直线运动
B.
液滴一定带正电
C.
电场线方向一定斜向上
D.
液滴一定做匀速直线运动